80 lines
856 B
Plaintext
80 lines
856 B
Plaintext
include 'gsos.equ'
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device_rw proc
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; inputs: a = call num
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; outputs: carry, a
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with dev_parms
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sta dev_callnum
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loop
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jsl dev_dispatcher
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bcc exit
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cmp #drvr_disk_sw
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beq loop
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cmp #drvr_busy
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beq loop
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sec
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exit
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rts
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endp
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device_read proc export
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lda #drvr_read
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bra device_rw
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endp
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device_write proc export
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lda #drvr_write
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bra device_rw
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endp
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;
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; inputs: a = block number. (1024 byte block)
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;
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;
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read_data_block proc export
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with dev_parms
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; reads a data block.
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; block 0 -> all zeros (sparse support)
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cmp #0
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bne read_it
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; a = 0!
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ldy #1024-2
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loop
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sta [dev_buff],y
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dey
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dey
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bpl loop
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clc
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rts
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read_it
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; a = block num (1024-byte).
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; multiply x 2 for 512-byte blocks.
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asl a
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sta dev_blk_num
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lda #0
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rol a
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sta dev_blk_num+2
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lda #1024
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;sta dev_blk_size
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sta dev_req_cnt
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stz dev_req_cnt+2
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bra device_read
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endp
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end
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