[150] | 1 | ; Project name : XTIDE Universal BIOS |
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| 2 | ; Description : Serial Device Command functions. |
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| 3 | |
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| 4 | ; Section containing code |
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| 5 | SECTION .text |
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| 6 | |
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[179] | 7 | ;--------------- UART Equates ----------------------------- |
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| 8 | ; |
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| 9 | ; Serial Programming References: |
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| 10 | ; http://en.wikibooks.org/wiki/Serial_Programming |
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| 11 | ; |
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[181] | 12 | |
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[179] | 13 | SerialCommand_UART_base EQU 0 |
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| 14 | SerialCommand_UART_transmitByte EQU 0 |
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| 15 | SerialCommand_UART_receiveByte EQU 0 |
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[216] | 16 | |
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| 17 | ; |
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[181] | 18 | ; Values for UART_divisorLow: |
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[179] | 19 | ; 60h = 1200, 30h = 2400, 18h = 4800, 0ch = 9600, 6 = 19200, 3 = 38400, 2 = 57600, 1 = 115200 |
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[216] | 20 | ; |
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| 21 | SerialCommand_UART_divisorLow EQU 0 |
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[179] | 22 | |
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[216] | 23 | ; |
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[179] | 24 | ; We support 4 baud rates, starting here going higher and skipping every other baud rate |
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| 25 | ; Starting with 30h, that means 30h (1200 baud), 0ch (9600 baud), 3 (38400 baud), and 1 (115200 baud) |
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| 26 | ; Note: hardware baud multipliers (2x, 4x) will impact the final baud rate and are not known at this level |
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[216] | 27 | ; |
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| 28 | SerialCommand_UART_divisorLow_startingBaud EQU 030h |
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[179] | 29 | |
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[181] | 30 | SerialCommand_UART_interruptEnable EQU 1 |
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[216] | 31 | |
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| 32 | ; |
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| 33 | ; UART_divisorHigh is zero for all speeds including and above 1200 baud (which is all we do) |
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| 34 | ; |
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[179] | 35 | SerialCommand_UART_divisorHigh EQU 1 |
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| 36 | |
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| 37 | SerialCommand_UART_interruptIdent EQU 2 |
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| 38 | SerialCommand_UART_FIFOControl EQU 2 |
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| 39 | |
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| 40 | SerialCommand_UART_lineControl EQU 3 |
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[181] | 41 | |
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[179] | 42 | SerialCommand_UART_modemControl EQU 4 |
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| 43 | |
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| 44 | SerialCommand_UART_lineStatus EQU 5 |
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| 45 | |
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| 46 | SerialCommand_UART_modemStatus EQU 6 |
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| 47 | |
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| 48 | SerialCommand_UART_scratch EQU 7 |
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| 49 | |
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| 50 | SerialCommand_Protocol_Write EQU 3 |
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| 51 | SerialCommand_Protocol_Read EQU 2 |
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| 52 | SerialCommand_Protocol_Inquire EQU 0 |
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| 53 | SerialCommand_Protocol_Header EQU 0a0h |
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[181] | 54 | |
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[150] | 55 | ;-------------------------------------------------------------------- |
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[179] | 56 | ; SerialCommand_OutputWithParameters |
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[150] | 57 | ; Parameters: |
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[179] | 58 | ; BH: Non-zero if 48-bit addressing used |
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| 59 | ; (ignored at present as 48-bit addressing is not supported) |
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| 60 | ; BL: IDE Status Register bit to poll after command |
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| 61 | ; (ignored at present, since there is no IDE status register to poll) |
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| 62 | ; ES:SI: Ptr to buffer (for data transfer commands) |
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| 63 | ; DS:DI: Ptr to DPT (in RAMVARS segment) |
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| 64 | ; SS:BP: Ptr to IDEREGS_AND_INTPACK |
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[150] | 65 | ; Returns: |
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| 66 | ; AH: INT 13h Error Code |
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| 67 | ; CF: Cleared if success, Set if error |
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| 68 | ; Corrupts registers: |
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[179] | 69 | ; AL, BX, CX, DX, (ES:SI for data transfer commands) |
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[150] | 70 | ;-------------------------------------------------------------------- |
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| 71 | ALIGN JUMP_ALIGN |
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[179] | 72 | SerialCommand_OutputWithParameters: |
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[181] | 73 | |
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[179] | 74 | mov ah,(SerialCommand_Protocol_Header | SerialCommand_Protocol_Read) |
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[181] | 75 | |
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[179] | 76 | mov al,[bp+IDEPACK.bCommand] |
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[150] | 77 | |
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[179] | 78 | cmp al,20h ; Read Sectors IDE command |
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| 79 | jz .readOrWrite |
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| 80 | inc ah ; now SerialCommand_Protocol_Write |
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| 81 | cmp al,30h ; Write Sectors IDE command |
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| 82 | jz .readOrWrite |
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[181] | 83 | |
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[179] | 84 | ; all other commands return success |
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| 85 | ; including function 0ech which should return drive information, this is handled with the identify functions |
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[216] | 86 | ; |
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[179] | 87 | xor ah,ah ; also clears carry |
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| 88 | ret |
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[181] | 89 | |
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| 90 | .readOrWrite: |
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[179] | 91 | mov [bp+IDEPACK.bFeatures],ah ; store protocol command |
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[181] | 92 | |
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| 93 | mov dl, byte [di+DPT.bSerialPortAndBaud] |
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| 94 | |
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[179] | 95 | ; fall-through |
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[150] | 96 | |
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| 97 | ;-------------------------------------------------------------------- |
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[179] | 98 | ; SerialCommand_OutputWithParameters_DeviceInDL |
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[150] | 99 | ; Parameters: |
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[181] | 100 | ; AH: Protocol Command |
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[179] | 101 | ; DL: Packed I/O port and baud rate |
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[150] | 102 | ; ES:SI: Ptr to buffer (for data transfer commands) |
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| 103 | ; SS:BP: Ptr to IDEREGS_AND_INTPACK |
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| 104 | ; Returns: |
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| 105 | ; AH: INT 13h Error Code |
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| 106 | ; CF: Cleared if success, Set if error |
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| 107 | ; Corrupts registers: |
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| 108 | ; AL, BX, CX, DX, (ES:SI for data transfer commands) |
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[181] | 109 | ;-------------------------------------------------------------------- |
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[179] | 110 | SerialCommand_OutputWithParameters_DeviceInDL: |
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[181] | 111 | |
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[179] | 112 | push si |
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| 113 | push di |
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| 114 | push bp |
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| 115 | push es |
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| 116 | |
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[181] | 117 | ; |
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[179] | 118 | ; Unpack I/O port and baud from DPT |
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| 119 | ; Port to DX more or less for the remainder of the routine |
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| 120 | ; Baud in CH until UART initialization is complete |
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| 121 | ; |
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[214] | 122 | mov dh, ((DEVICE_SERIAL_PACKEDPORTANDBAUD_STARTINGPORT & 0f00h) >> (8+1)) |
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| 123 | shl dx, 1 ; port offset already x4, needs one more shift to be x8 |
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[179] | 124 | mov cl, dl |
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[181] | 125 | |
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[214] | 126 | and cl, (DEVICE_SERIAL_PACKEDPORTANDBAUD_BAUDMASK << 1) |
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[179] | 127 | mov ch, SerialCommand_UART_divisorLow_startingBaud |
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| 128 | shr ch, cl |
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| 129 | adc ch, 0 |
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| 130 | |
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[214] | 131 | and dl, ((DEVICE_SERIAL_PACKEDPORTANDBAUD_PORTMASK << 1) & 0ffh) |
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| 132 | add dx, byte (DEVICE_SERIAL_PACKEDPORTANDBAUD_STARTINGPORT & 0ffh) |
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[179] | 133 | |
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| 134 | mov al,[bp+IDEPACK.bSectorCount] |
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| 135 | |
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| 136 | ; |
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| 137 | ; Command byte and sector count live at the top of the stack, pop/push are used to access |
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[181] | 138 | ; |
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[179] | 139 | push ax |
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| 140 | |
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[216] | 141 | %if 0 |
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| 142 | cld ; Shouldn't be needed. DF has already been cleared (line 24, Int13h.asm) |
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| 143 | %endif |
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[181] | 144 | |
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[179] | 145 | ;---------------------------------------------------------------------- |
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| 146 | ; |
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| 147 | ; Initialize UART |
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| 148 | ; |
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[181] | 149 | ; We do this each time since DOS (at boot) or another program may have |
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[179] | 150 | ; decided to reprogram the UART |
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| 151 | ; |
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[214] | 152 | mov bl,dl ; setup BL with proper values for read/write loops (BH comes later) |
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| 153 | |
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[179] | 154 | mov al,83h |
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| 155 | add dl,SerialCommand_UART_lineControl |
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| 156 | out dx,al |
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| 157 | |
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| 158 | mov al,ch |
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[214] | 159 | mov dl,bl ; divisor low |
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[179] | 160 | out dx,al |
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| 161 | |
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| 162 | xor ax,ax |
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| 163 | inc dx ; divisor high |
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| 164 | push dx |
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| 165 | out dx,al |
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| 166 | |
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| 167 | mov al,047h |
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| 168 | inc dx ; fifo |
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[181] | 169 | out dx,al |
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[179] | 170 | |
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| 171 | mov al,03h |
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| 172 | inc dx ; linecontrol |
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| 173 | out dx,al |
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| 174 | |
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| 175 | mov al,0bh |
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| 176 | inc dx ; modemcontrol |
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| 177 | out dx,al |
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| 178 | |
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[214] | 179 | inc dx ; linestatus (no output now, just setting up BH for later use) |
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| 180 | mov bh,dl |
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| 181 | |
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[179] | 182 | pop dx ; base, interrupts disabled |
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| 183 | xor ax,ax |
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| 184 | out dx,al |
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| 185 | |
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| 186 | ;---------------------------------------------------------------------- |
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| 187 | ; |
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| 188 | ; Send Command |
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| 189 | ; |
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| 190 | ; Sends first six bytes of IDEREGS_AND_INTPACK as the command |
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| 191 | ; |
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| 192 | push es ; save off real buffer location |
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[214] | 193 | push si |
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[181] | 194 | |
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[214] | 195 | mov si,bp ; point to IDEREGS for command dispatch; |
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[179] | 196 | push ss |
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| 197 | pop es |
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| 198 | |
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[214] | 199 | mov di,0ffffh ; initialize checksum for write |
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| 200 | mov bp,di |
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[179] | 201 | |
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[214] | 202 | mov cx,4 ; writing 3 words (plus 1) |
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[181] | 203 | |
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[214] | 204 | cli ; interrupts off... |
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[179] | 205 | |
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[214] | 206 | call SerialCommand_WriteProtocol.entry |
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| 207 | |
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| 208 | pop di ; restore real buffer location (note change from SI to DI) |
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| 209 | ; Buffer is primarily referenced through ES:DI throughout, since |
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| 210 | ; we need to store (read sector) faster than we read (write sector) |
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[179] | 211 | pop es |
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| 212 | |
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[214] | 213 | .nextSectorNormalize: |
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| 214 | |
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| 215 | call Registers_NormalizeESDI |
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| 216 | |
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[179] | 217 | pop ax ; load command byte (done before call to .nextSector on subsequent iterations) |
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| 218 | push ax |
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| 219 | |
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| 220 | ; |
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| 221 | ; Top of the read/write loop, one iteration per sector |
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[181] | 222 | ; |
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[179] | 223 | .nextSector: |
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[214] | 224 | mov si,0ffffh ; initialize checksum for read or write |
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[179] | 225 | mov bp,si |
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| 226 | |
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[214] | 227 | mov cx,0101h ; writing 256 words (plus 1) |
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[181] | 228 | |
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[179] | 229 | shr ah,1 ; command byte, are we doing a write? |
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[214] | 230 | jnc .readEntry |
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[181] | 231 | |
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[214] | 232 | xchg si,di |
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| 233 | call SerialCommand_WriteProtocol.entry |
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| 234 | xchg si,di |
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[179] | 235 | |
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[214] | 236 | inc cx ; CX = 1 now (0 out of WriteProtocol) |
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| 237 | jmp .readEntry |
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[181] | 238 | |
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[179] | 239 | ;---------------------------------------------------------------------- |
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| 240 | ; |
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| 241 | ; Timeout |
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| 242 | ; |
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| 243 | ; To save code space, we use the contents of DL to decide which byte in the word to return for reading. |
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| 244 | ; |
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| 245 | .readTimeout: |
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[214] | 246 | push ax ; not only does this push preserve AX (which we need), but it also |
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| 247 | ; means the stack has the same number of bytes on it as when we are |
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| 248 | ; sending a packet, important for error cleanup and exit |
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| 249 | mov ah,1 |
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| 250 | call SerialCommand_WaitAndPoll_Read |
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| 251 | pop ax |
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[179] | 252 | test dl,1 |
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| 253 | jz .readByte1Ready |
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[214] | 254 | jmp .readByte2Ready |
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[179] | 255 | |
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| 256 | ;---------------------------------------------------------------------------- |
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| 257 | ; |
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| 258 | ; Read Block (without interrupts, used when there is a FIFO, high speed) |
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| 259 | ; |
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[181] | 260 | ; NOTE: This loop is very time sensitive. Literally, another instruction |
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[179] | 261 | ; cannot be inserted into this loop without us falling behind at high |
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[181] | 262 | ; speed (460.8K baud) on a 4.77Mhz 8088, making it hard to receive |
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[179] | 263 | ; a full 512 byte block. |
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| 264 | ; |
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[181] | 265 | .readLoop: |
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| 266 | stosw ; store word in caller's data buffer |
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| 267 | |
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[179] | 268 | add bp, ax ; update Fletcher's checksum |
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| 269 | adc bp, 0 |
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| 270 | add si, bp |
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| 271 | adc si, 0 |
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| 272 | |
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[214] | 273 | .readEntry: |
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[181] | 274 | mov dl,bh |
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| 275 | in al,dx |
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[179] | 276 | shr al,1 ; data ready (byte 1)? |
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[181] | 277 | mov dl,bl ; get ready to read data |
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[179] | 278 | jnc .readTimeout ; nope not ready, update timeouts |
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[181] | 279 | |
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| 280 | ; |
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[179] | 281 | ; Entry point after initial timeout. We enter here so that the checksum word |
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| 282 | ; is not stored (and is left in AX after the loop is complete). |
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[181] | 283 | ; |
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| 284 | .readByte1Ready: |
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[179] | 285 | in al, dx ; read data byte 1 |
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| 286 | |
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| 287 | mov ah, al ; store byte in ah for now |
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[181] | 288 | |
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[179] | 289 | ; |
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[181] | 290 | ; note the placement of this reset of dl to bh, and that it is |
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| 291 | ; before the return, which is assymetric with where this is done |
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| 292 | ; above for byte 1. The value of dl is used by the timeout routine |
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| 293 | ; to know which byte to return to (.read_byte1_ready or |
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[179] | 294 | ; .read_byte2_ready) |
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| 295 | ; |
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[181] | 296 | mov dl,bh |
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| 297 | |
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[179] | 298 | in al,dx |
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| 299 | shr al,1 ; data ready (byte 2)? |
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| 300 | jnc .readTimeout |
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[181] | 301 | .readByte2Ready: |
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| 302 | mov dl,bl |
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[179] | 303 | in al, dx ; read data byte 2 |
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| 304 | |
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| 305 | xchg al, ah ; ah was holding byte 1, reverse byte order |
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[181] | 306 | |
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[179] | 307 | loop .readLoop |
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| 308 | |
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[214] | 309 | sti ; interrupts back on ASAP, between packets |
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[181] | 310 | |
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[179] | 311 | ; |
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| 312 | ; Compare checksums |
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[181] | 313 | ; |
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[208] | 314 | xchg ax,bp |
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| 315 | xor ah,al |
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| 316 | mov cx,si |
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| 317 | xor cl,ch |
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| 318 | mov al,cl |
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[179] | 319 | cmp ax,bp |
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| 320 | jnz SerialCommand_OutputWithParameters_Error |
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| 321 | |
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| 322 | pop ax ; sector count and command byte |
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| 323 | dec al ; decrememnt sector count |
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| 324 | push ax ; save |
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[216] | 325 | jz SerialCommand_OutputWithParameters_ReturnCodeInALCF ; CF=0 from "cmp ax,bp" returning Zero above |
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[181] | 326 | |
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[179] | 327 | cli ; interrupts back off for ACK byte to host |
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| 328 | ; (host could start sending data immediately) |
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| 329 | out dx,al ; ACK with next sector number |
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[181] | 330 | |
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[214] | 331 | ; |
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[216] | 332 | ; Normalize buffer pointer for next go round, if needed. |
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[214] | 333 | ; |
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[216] | 334 | ; We need to re-nomrlize the pointer in ES:DI after processing every 7f sectors. That number could |
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| 335 | ; have been 80 if we knew the offset was on a segment boundary, but this may not be the case. |
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| 336 | ; |
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| 337 | ; We re-normalize based on the sector count (flags from "dec al" above)... |
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| 338 | ; a) we normalize before the first sector goes out, immediately after sending the command packet (above) |
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| 339 | ; b) on transitions from FF to FE, very rare case for writing 255 or 256 sectors |
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| 340 | ; c) on transitions from 80 to 7F, a large read/write |
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| 341 | ; d) on transitions from 00 to FF, very, very rare case of writing 256 secotrs |
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| 342 | ; We don't need to renormalize in this case, but it isn't worth the memory/effort to not do |
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| 343 | ; the extra work, and it does no harm. |
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| 344 | ; |
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| 345 | ; I really don't care much about (d) because I have not seen cases where any OS makes a request |
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| 346 | ; for more than 127 sectors. Back in the day, it appears that some BIOS could not support more than 127 |
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| 347 | ; sectors, so that may be the practical limit for OS and application developers. The Extended BIOS |
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| 348 | ; function also appear to be capped at 127 sectors. So although this can support the full 256 sectors |
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| 349 | ; if needed, we are optimized for that 1-127 range. |
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| 350 | ; |
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| 351 | ; Assume we start with 0000:000f, with 256 sectors to write... |
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| 352 | ; After first packet, 0000:020f |
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| 353 | ; First decrement of AL, transition from 00 to FF: renormalize to 0020:000f (unnecessary) |
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| 354 | ; After second packet, 0020:020f |
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| 355 | ; Second derement of AL, transition from FF to FE: renormalize to 0040:000f |
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| 356 | ; After 7f more packets, 0040:fe0f |
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| 357 | ; Decrement of AL, transition from 80 to 7F: renormalize to 1020:000f |
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| 358 | ; After 7f more packets, 1020:fe0f or 2000:000f if normalized |
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| 359 | ; Decrement of AL, from 1 to 0: exit |
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| 360 | ; |
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| 361 | jge short .nextSector ; OF=SF, branch for 1-7e, most common case |
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| 362 | ; (0 kicked out above for return success) |
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[179] | 363 | |
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[216] | 364 | add al,2 ; 7f-ff moves to 81-01 |
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| 365 | ; (0-7e kicked out before we get here) |
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| 366 | ; 7f moves to 81 and OF=1, so OF=SF |
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| 367 | ; fe moves to 0 and OF=0, SF=0, so OF=SF |
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| 368 | ; ff moves to 1 and OF=0, SF=0, so OF=SF |
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| 369 | ; 80-fd moves to 82-ff and OF=0, so OF<>SF |
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| 370 | |
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| 371 | jl short .nextSector ; OF<>SF, branch for all cases but 7f, fe, and ff |
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| 372 | |
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| 373 | %if 0 |
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| 374 | jpo short .nextSector ; if we really wanted to avoid normalizing for ff, this |
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| 375 | ; is one way to do it, but it adds more memory and more |
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| 376 | ; cycles for the 7f and fe cases. IMHO, given that I've |
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| 377 | ; never seen a request for more than 7f, this seems unnecessary. |
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| 378 | %endif |
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| 379 | |
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| 380 | jmp short .nextSectorNormalize ; our two renormalization cases (plus one for ff) |
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| 381 | |
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[179] | 382 | ;--------------------------------------------------------------------------- |
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| 383 | ; |
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| 384 | ; Cleanup, error reporting, and exit |
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| 385 | ; |
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[181] | 386 | |
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| 387 | ; |
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[179] | 388 | ; Used in situations where a call is underway, such as with SerialCommand_WaitAndPoll |
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[181] | 389 | ; |
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[214] | 390 | ALIGN JUMP_ALIGN |
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| 391 | SerialCommand_OutputWithParameters_ErrorAndPop4Words: |
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| 392 | add sp,8 |
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[216] | 393 | ;;; fall-through |
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[179] | 394 | |
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[214] | 395 | ALIGN JUMP_ALIGN |
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[181] | 396 | SerialCommand_OutputWithParameters_Error: |
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[216] | 397 | ;---------------------------------------------------------------------- |
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| 398 | ; |
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| 399 | ; Clear read buffer |
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| 400 | ; |
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| 401 | ; In case there are extra characters or an error in the FIFO, clear it out. |
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| 402 | ; In theory the initialization of the UART registers above should have |
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| 403 | ; taken care of this, but I have seen cases where this is not true. |
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| 404 | ; |
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| 405 | .clearBuffer: |
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| 406 | mov dl,bh |
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| 407 | in al,dx |
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| 408 | mov dl,bl |
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| 409 | test al,08fh |
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| 410 | jz .clearBufferComplete |
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| 411 | shr al,1 |
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| 412 | in al,dx |
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| 413 | jc .clearBuffer ; note CF from shr above |
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| 414 | |
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| 415 | .clearBufferComplete: |
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[181] | 416 | stc |
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[179] | 417 | mov al,1 |
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| 418 | |
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[214] | 419 | ALIGN JUMP_ALIGN |
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[181] | 420 | SerialCommand_OutputWithParameters_ReturnCodeInALCF: |
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[216] | 421 | %if 0 |
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| 422 | sti ; all paths here will already have interrupts turned back on |
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| 423 | %endif |
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[179] | 424 | mov ah,al |
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| 425 | |
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[214] | 426 | pop bp ; recover ax (command and count) from stack, throw away |
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[179] | 427 | |
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| 428 | pop es |
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| 429 | pop bp |
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| 430 | pop di |
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| 431 | pop si |
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| 432 | |
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| 433 | ret |
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| 434 | |
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[150] | 435 | ;-------------------------------------------------------------------- |
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[214] | 436 | ; SerialCommand_WriteProtocol |
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[179] | 437 | ; |
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[214] | 438 | ; NOTE: As with its read counterpart, this loop is very time sensitive. |
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| 439 | ; Although it will still function, adding additional instructions will |
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| 440 | ; impact the write througput, especially on slower machines. |
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| 441 | ; |
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[179] | 442 | ; Parameters: |
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[214] | 443 | ; ES:SI: Ptr to buffer |
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| 444 | ; CX: Words to write, plus 1 |
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| 445 | ; BP/DI: Initialized for Checksum (-1 in each) |
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| 446 | ; DH: I/O Port high byte |
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| 447 | ; BX: LineStatus Register address (BH) and Receive/Transmit Register address (BL) |
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[179] | 448 | ; Returns: |
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[214] | 449 | ; BP/DI: Checksum for written bytes, compared against ACK from server in .readLoop |
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| 450 | ; CX: Zero |
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| 451 | ; DL: Receive/Transmit Register address |
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[181] | 452 | ; Corrupts registers: |
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[214] | 453 | ; AX |
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[179] | 454 | ;-------------------------------------------------------------------- |
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[214] | 455 | ALIGN JUMP_ALIGN |
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| 456 | SerialCommand_WriteProtocol: |
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| 457 | .writeLoop: |
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| 458 | es lodsw ; fetch next word |
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[179] | 459 | |
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[214] | 460 | out dx,al ; output first byte |
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[179] | 461 | |
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[214] | 462 | add bp,ax ; update checksum |
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| 463 | adc bp,0 |
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| 464 | add di,bp |
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| 465 | adc di,0 |
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[181] | 466 | |
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[214] | 467 | mov dl,bh ; transmit buffer empty? |
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[179] | 468 | in al,dx |
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[214] | 469 | test al,20h |
---|
| 470 | jz .writeTimeout2 ; nope, use our polling routine |
---|
[181] | 471 | |
---|
[214] | 472 | .writeByte2Ready: |
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| 473 | mov dl,bl |
---|
| 474 | mov al,ah ; output second byte |
---|
| 475 | out dx,al |
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| 476 | |
---|
| 477 | .entry: |
---|
| 478 | mov dl,bh ; transmit buffer empty? |
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| 479 | in al,dx |
---|
| 480 | test al,20h |
---|
| 481 | mov dl,bl |
---|
| 482 | jz .writeTimeout1 ; nope, use our polling routine |
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| 483 | |
---|
| 484 | .writeByte1Ready: |
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| 485 | loop .writeLoop |
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| 486 | |
---|
| 487 | mov ax,di ; fold Fletcher's checksum and output |
---|
| 488 | xor al,ah |
---|
| 489 | out dx,al ; byte 1 |
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| 490 | |
---|
| 491 | call SerialCommand_WaitAndPoll_Write |
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| 492 | |
---|
| 493 | mov ax,bp |
---|
| 494 | xor al,ah |
---|
| 495 | out dx,al ; byte 2 |
---|
| 496 | |
---|
[179] | 497 | ret |
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| 498 | |
---|
[214] | 499 | .writeTimeout2: |
---|
| 500 | mov dl,ah ; need to preserve AH, but don't need DL (will be reset upon return) |
---|
| 501 | call SerialCommand_WaitAndPoll_Write |
---|
| 502 | mov ah,dl |
---|
| 503 | jmp .writeByte2Ready |
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| 504 | |
---|
| 505 | .writeTimeout1: |
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| 506 | mov ax,.writeByte1Ready |
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| 507 | push ax ; return address for ret at end of SC_writeTimeout2 |
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| 508 | ;;; fall-through |
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| 509 | |
---|
[179] | 510 | ;-------------------------------------------------------------------- |
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[214] | 511 | ; SerialCommand_WaitAndPoll |
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[179] | 512 | ; |
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| 513 | ; Parameters: |
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[214] | 514 | ; AH: UART_LineStatus bit to test (20h for write, or 1h for read) |
---|
| 515 | ; One entry point fills in AH with 20h for write |
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| 516 | ; DX: Port address (OK if already incremented to UART_lineStatus) |
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| 517 | ; BX: |
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| 518 | ; Stack: 2 words on the stack below the command/count word |
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[179] | 519 | ; Returns: |
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[214] | 520 | ; Returns when desired UART_LineStatus bit is cleared |
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| 521 | ; Jumps directly to error exit if timeout elapses (and cleans up stack) |
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[179] | 522 | ; Corrupts registers: |
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[214] | 523 | ; AX |
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[179] | 524 | ;-------------------------------------------------------------------- |
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[181] | 525 | |
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[214] | 526 | SerialCommand_WaitAndPoll_SoftDelayTicks EQU 20 |
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[181] | 527 | |
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[214] | 528 | ALIGN JUMP_ALIGN |
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| 529 | SerialCommand_WaitAndPoll_Write: |
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| 530 | mov ah,20h |
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| 531 | ;;; fall-through |
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[181] | 532 | |
---|
[214] | 533 | ALIGN JUMP_ALIGN |
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| 534 | SerialCommand_WaitAndPoll_Read: |
---|
| 535 | push cx |
---|
| 536 | push dx |
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[150] | 537 | |
---|
[214] | 538 | ; |
---|
| 539 | ; We first poll in a tight loop, interrupts off, for the next character to come in/be sent |
---|
| 540 | ; |
---|
| 541 | xor cx,cx |
---|
| 542 | .readTimeoutLoop: |
---|
| 543 | mov dl,bh |
---|
| 544 | in al,dx |
---|
| 545 | test al,ah |
---|
| 546 | jnz .readTimeoutComplete |
---|
| 547 | loop .readTimeoutLoop |
---|
[181] | 548 | |
---|
[214] | 549 | ; |
---|
| 550 | ; If that loop completes, then we assume there is a long delay involved, turn interrupts back on |
---|
| 551 | ; and wait for a given number of timer ticks to pass. |
---|
| 552 | ; |
---|
| 553 | sti |
---|
| 554 | mov cl,SerialCommand_WaitAndPoll_SoftDelayTicks |
---|
| 555 | call Timer_InitializeTimeoutWithTicksInCL |
---|
| 556 | .WaitAndPoll: |
---|
| 557 | call Timer_SetCFifTimeout |
---|
| 558 | jc SerialCommand_OutputWithParameters_ErrorAndPop4Words |
---|
| 559 | in al,dx |
---|
| 560 | test al,ah |
---|
| 561 | jz .WaitAndPoll |
---|
| 562 | cli |
---|
[150] | 563 | |
---|
[214] | 564 | .readTimeoutComplete: |
---|
| 565 | pop dx |
---|
| 566 | pop cx |
---|
| 567 | ret |
---|
[181] | 568 | |
---|
[179] | 569 | ;-------------------------------------------------------------------- |
---|
| 570 | ; SerialCommand_IdentifyDeviceToBufferInESSIwithDriveSelectByteInBH |
---|
| 571 | ; Parameters: |
---|
| 572 | ; BH: Drive Select byte for Drive and Head Select Register |
---|
| 573 | ; DS: Segment to RAMVARS |
---|
| 574 | ; ES:SI: Ptr to buffer to receive 512-byte IDE Information |
---|
| 575 | ; CS:BP: Ptr to IDEVARS |
---|
| 576 | ; Returns: |
---|
| 577 | ; AH: INT 13h Error Code |
---|
[203] | 578 | ; NOTE: Not set (or checked) during drive detection |
---|
[179] | 579 | ; CF: Cleared if success, Set if error |
---|
| 580 | ; Corrupts registers: |
---|
| 581 | ; AL, BL, CX, DX, SI, DI, ES |
---|
| 582 | ;-------------------------------------------------------------------- |
---|
| 583 | ALIGN JUMP_ALIGN |
---|
| 584 | SerialCommand_IdentifyDeviceToBufferInESSIwithDriveSelectByteInBH: |
---|
[203] | 585 | ; |
---|
| 586 | ; To improve boot time, we do our best to avoid looking for slave serial drives when we already know the results |
---|
| 587 | ; from the looking for a master. This is particuarly true when doing a COM port scan, as we will end up running |
---|
| 588 | ; through all the COM ports and baud rates a second time. |
---|
| 589 | ; |
---|
| 590 | ; But drive detection isn't the only case - we also need to get the right drive when called on int13h/25h. |
---|
| 591 | ; |
---|
| 592 | ; The decision tree: |
---|
| 593 | ; |
---|
| 594 | ; Master: |
---|
| 595 | ; bSerialPackedPortAndBaud Non-Zero: -> Continue with bSerialPackedAndBaud (1) |
---|
| 596 | ; bSerialPackedPortAndBaud Zero: |
---|
| 597 | ; bLastSerial Zero: -> Scan (2) |
---|
| 598 | ; bLastSerial Non-Zero: -> Continue with bLastSerial (3) |
---|
| 599 | ; |
---|
| 600 | ; Slave: |
---|
| 601 | ; bSerialPackedPortAndBaud Non-Zero: |
---|
| 602 | ; bLastSerial Zero: -> Error - Not Found (4) |
---|
| 603 | ; bLastSerial Non-Zero: -> Continue with bSerialPackedAndBaud (5) |
---|
| 604 | ; bSerialPackedPortAndBaud Zero: |
---|
| 605 | ; bLastSerial Zero: -> Error - Not Found (4) |
---|
| 606 | ; bLastSerial Non-Zero: -> Continue with bLastSerial (6) |
---|
| 607 | ; |
---|
| 608 | ; (1) This was a port/baud that was explicilty set with the configurator. In the drive detection case, as this |
---|
| 609 | ; is the Master, we are checking out a new controller, and so don't care about the value of bLastSerial. |
---|
| 610 | ; And as with the int13h/25h case, we just go off and get the needed information using the user's setting. |
---|
| 611 | ; (2) We are using the special .ideVarsSerialAuto strucutre. During drive detection, we would only be here |
---|
| 612 | ; if bLastSerial is zero (since we only scan if no explicit drives are set), so we go off to scan. |
---|
| 613 | ; (3) We are using the special .ideVarsSerialAuto strucutre. We won't get here during drive detection, but |
---|
| 614 | ; we might get here on an int13h/25h call. If we have scanned COM drives, they are the ONLY serial drives |
---|
| 615 | ; in use, and so bLastSerial will reflect the port/baud setting for the scanned COM drives. |
---|
| 616 | ; (4) No master has been found yet, therefore no slave should be found. Avoiding the slave reduces boot time, |
---|
| 617 | ; especially in the full COM port scan case. Note that this is different from the hardware IDE, where we |
---|
| 618 | ; will scan for a slave even if a master is not present. Note that if ANY master had been previously found, |
---|
| 619 | ; we will do the slave scan, which isn't harmful, it just wates time. But the most common case (by a wide |
---|
| 620 | ; margin) will be just one serial controller. |
---|
| 621 | ; (5) A COM port scan for a master had been previously completed, and a drive was found. In a multiple serial |
---|
| 622 | ; controller scenario being called with int13h/25h, we need to use the value in bSerialPackedPortAndBaud |
---|
| 623 | ; to make sure we get the proper drive. |
---|
| 624 | ; (6) A COM port scan for a master had been previously completed, and a drive was found. We would only get here |
---|
| 625 | ; if no serial drive was explicitly set by the user in the configurator or that drive had not been found. |
---|
| 626 | ; Instead of performing the full COM port scan for the slave, use the port/baud value stored during the |
---|
| 627 | ; master scan. |
---|
| 628 | ; |
---|
| 629 | mov dl,[cs:bp+IDEVARS.bSerialPackedPortAndBaud] |
---|
| 630 | mov al, byte [RAMVARS.xlateVars+XLATEVARS.bLastSerial] |
---|
| 631 | |
---|
| 632 | test bh, FLG_DRVNHEAD_DRV |
---|
| 633 | jz .master |
---|
[179] | 634 | |
---|
[203] | 635 | test al,al ; Take care of the case that is different between master and slave. |
---|
| 636 | jz .error ; Because we do this here, the jz after the "or" below will not be taken |
---|
| 637 | |
---|
| 638 | ; fall-through |
---|
| 639 | .master: |
---|
[196] | 640 | test dl,dl |
---|
[203] | 641 | jnz .identifyDeviceInDL |
---|
[179] | 642 | |
---|
[203] | 643 | or dl,al ; Move bLast into position in dl, as well as test for zero |
---|
| 644 | jz .scanSerial |
---|
[199] | 645 | |
---|
[179] | 646 | ; fall-through |
---|
[203] | 647 | .identifyDeviceInDL: |
---|
[179] | 648 | |
---|
| 649 | push bp ; setup fake IDEREGS_AND_INTPACK |
---|
| 650 | |
---|
| 651 | push dx |
---|
| 652 | |
---|
| 653 | mov cl,1 ; 1 sector to move |
---|
| 654 | push cx |
---|
| 655 | |
---|
| 656 | mov bl,0a0h ; protocol command to ah and onto stack with bh |
---|
| 657 | mov ah,bl |
---|
[181] | 658 | |
---|
[179] | 659 | push bx |
---|
| 660 | |
---|
| 661 | mov bp,sp |
---|
| 662 | call SerialCommand_OutputWithParameters_DeviceInDL |
---|
| 663 | |
---|
| 664 | pop bx |
---|
[181] | 665 | |
---|
| 666 | pop cx |
---|
[179] | 667 | pop dx |
---|
| 668 | |
---|
| 669 | pop bp |
---|
[203] | 670 | ; |
---|
| 671 | ; place packed port/baud in RAMVARS, read by FinalizeDPT and DetectDrives |
---|
| 672 | ; |
---|
| 673 | ; Note that this will be set during an int13h/25h call as well. Which is OK since it is only used (at the |
---|
| 674 | ; top of this routine) for drives found during a COM scan, and we only COM scan if there were no other |
---|
| 675 | ; COM drives found. So we will only reaffirm the port/baud for the one COM port/baud that has a drive. |
---|
| 676 | ; |
---|
| 677 | jc .notFound ; only store bLastSerial if success |
---|
| 678 | mov byte [RAMVARS.xlateVars+XLATEVARS.bLastSerial], dl |
---|
[179] | 679 | |
---|
[203] | 680 | .notFound: |
---|
[179] | 681 | ret |
---|
| 682 | |
---|
| 683 | ;---------------------------------------------------------------------- |
---|
| 684 | ; |
---|
| 685 | ; SerialCommand_AutoSerial |
---|
| 686 | ; |
---|
| 687 | ; When the SerialAuto IDEVARS entry is used, scans the COM ports on the machine for a possible serial connection. |
---|
[181] | 688 | ; |
---|
| 689 | |
---|
[203] | 690 | .scanPortAddresses: db DEVICE_SERIAL_COM7 >> 2 |
---|
| 691 | db DEVICE_SERIAL_COM6 >> 2 |
---|
| 692 | db DEVICE_SERIAL_COM5 >> 2 |
---|
| 693 | db DEVICE_SERIAL_COM4 >> 2 |
---|
| 694 | db DEVICE_SERIAL_COM3 >> 2 |
---|
| 695 | db DEVICE_SERIAL_COM2 >> 2 |
---|
| 696 | db DEVICE_SERIAL_COM1 >> 2 |
---|
| 697 | db 0 |
---|
[179] | 698 | |
---|
[181] | 699 | ALIGN JUMP_ALIGN |
---|
[203] | 700 | .scanSerial: |
---|
| 701 | mov di,.scanPortAddresses-1 |
---|
[181] | 702 | |
---|
[179] | 703 | .nextPort: |
---|
| 704 | inc di ; load next port address |
---|
| 705 | mov dl,[cs:di] |
---|
[181] | 706 | |
---|
[179] | 707 | mov dh,0 ; shift from one byte to two |
---|
[181] | 708 | eSHL_IM dx, 2 |
---|
[203] | 709 | jz .error |
---|
[179] | 710 | |
---|
| 711 | ; |
---|
| 712 | ; Test for COM port presence, write to and read from registers |
---|
[181] | 713 | ; |
---|
| 714 | push dx |
---|
[179] | 715 | add dl,SerialCommand_UART_lineControl |
---|
| 716 | mov al, 09ah |
---|
| 717 | out dx, al |
---|
| 718 | in al, dx |
---|
| 719 | pop dx |
---|
| 720 | cmp al, 09ah |
---|
[181] | 721 | jnz .nextPort |
---|
[179] | 722 | |
---|
| 723 | mov al, 0ch |
---|
| 724 | out dx, al |
---|
| 725 | in al, dx |
---|
| 726 | cmp al, 0ch |
---|
| 727 | jnz .nextPort |
---|
| 728 | |
---|
| 729 | ; |
---|
| 730 | ; Pack into dl, baud rate starts at 0 |
---|
[181] | 731 | ; |
---|
[199] | 732 | add dx,-(DEVICE_SERIAL_PACKEDPORTANDBAUD_STARTINGPORT) |
---|
| 733 | shr dx,1 ; dh is zero at this point, and will be sent to the server, |
---|
| 734 | ; so we know this is an auto detect |
---|
[181] | 735 | |
---|
[179] | 736 | jmp .testFirstBaud |
---|
| 737 | |
---|
| 738 | ; |
---|
| 739 | ; Walk through 4 possible baud rates |
---|
[181] | 740 | ; |
---|
| 741 | .nextBaud: |
---|
[179] | 742 | inc dx |
---|
| 743 | test dl,3 |
---|
| 744 | jz .nextPort |
---|
[181] | 745 | |
---|
| 746 | .testFirstBaud: |
---|
[203] | 747 | call .identifyDeviceInDL |
---|
[179] | 748 | jc .nextBaud |
---|
| 749 | |
---|
| 750 | ret |
---|
[181] | 751 | |
---|
[203] | 752 | .error: |
---|
[181] | 753 | stc |
---|
[216] | 754 | %if 0 |
---|
| 755 | mov ah,1 ; setting the error code is unnecessary as this path can only be taken during |
---|
| 756 | ; drive detection, and drive detection works off CF and does not check AH |
---|
| 757 | %endif |
---|
[203] | 758 | ret |
---|
[179] | 759 | |
---|
[203] | 760 | |
---|