1 | ; Project name : XTIDE Universal BIOS |
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2 | ; Description : Int 13h function AH=Ch, Seek. |
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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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7 | ;-------------------------------------------------------------------- |
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8 | ; Int 13h function AH=Ch, Seek. |
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9 | ; |
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10 | ; AHCh_HandlerForSeek |
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11 | ; Parameters: |
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12 | ; CX, DH: Same as in INTPACK |
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13 | ; DL: Translated Drive number |
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14 | ; DS:DI: Ptr to DPT (in RAMVARS segment) |
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15 | ; SS:BP: Ptr to INTPACK |
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16 | ; Parameters on INTPACK in SS:BP: |
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17 | ; CH: Cylinder number, bits 7...0 |
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18 | ; CL: Bits 7...6: Cylinder number bits 9 and 8 |
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19 | ; Bits 5...0: Starting sector number (1...63) |
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20 | ; DH: Starting head number (0...255) |
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21 | ; Returns with INTPACK in SS:BP: |
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22 | ; AH: BIOS Error code |
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23 | ; CF: 0 if succesfull, 1 if error |
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24 | ;-------------------------------------------------------------------- |
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25 | ALIGN JUMP_ALIGN |
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26 | AHCh_HandlerForSeek: |
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27 | %ifndef USE_186 |
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28 | call AHCh_SeekToCylinder |
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29 | jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH |
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30 | %else |
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31 | push Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH |
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32 | ; Fall through to AHCh_SeekToCylinder |
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33 | %endif |
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34 | |
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35 | |
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36 | ;-------------------------------------------------------------------- |
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37 | ; AHCh_SeekToCylinder |
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38 | ; Parameters: |
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39 | ; CH: Cylinder number, bits 7...0 |
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40 | ; CL: Bits 7...6: Cylinder number bits 9 and 8 |
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41 | ; Bits 5...0: Starting sector number (1...63) |
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42 | ; DH: Starting head number (0...255) |
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43 | ; DS:DI: Ptr to DPT (in RAMVARS segment) |
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44 | ; Returns: |
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45 | ; AH: BIOS Error code |
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46 | ; CF: 0 if succesfull, 1 if error |
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47 | ; Corrupts registers: |
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48 | ; AL, BX, CX, DX |
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49 | ;-------------------------------------------------------------------- |
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50 | AHCh_SeekToCylinder: |
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51 | mov ax, HCMD_SEEK<<8 ; Load cmd to AH, AL=zero sector cnt |
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52 | call HCommand_OutputCountAndLCHSandCommand |
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53 | jc SHORT .ReturnWithErrorCodeInAH |
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54 | mov bx, di ; DS:BX now points to DPT |
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55 | jmp HStatus_WaitIrqOrRdy ; Wait for IRQ or RDY |
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56 | .ReturnWithErrorCodeInAH: |
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57 | ret |
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