CBDOS refactoring

src/dos_m65/pseudoiec/msg_acptr.s

@@ -0,0 +1,182 @@
+
+;
+; Implementation of ACPTR command. For detailed description see 'm65dos_bridge.s' file.
+;
+
+
+msg_ACPTR:
+
+	jsr dos_ENTER
+
+	; Check if there is a talker active
+
+	ldx IDX1_TALKER
+	+bmi msg_ACPTR_fail_no_talker
+
+	; Check if active channel is status one
+
+	lda XX_CHANNEL, X
+	cmp #$0F
+	+beq msg_ACPTR_status
+
+	; XXX add support for read contexts (multiple channels)
+
+	; Not a status channel - check if we have something to read out
+
+	ldx IDX2_TALKER
+	lda XX_ACPTR_LEN+0,x
+	ora XX_ACPTR_LEN+1,x
+	+beq msg_ACPTR_fail_no_data
+
+	; Read a byte of data from the buffer
+
+	jmp (msg_ACPTR_read_vectab, X)
+
+msg_ACPTR_read_SD:
+
+	; Read and return one byte
+
+	jsr SD_ACPTR_helper
+	sta TBTCNT
+	sta REG_A
+
+	; Increment pointer, decrement length
+
+	inc SD_ACPTR_PTR+0
+	bne @1
+	inc SD_ACPTR_PTR+1
+@1:
+	dec SD_ACPTR_LEN+0
+	lda SD_ACPTR_LEN+0
+	cmp #$FF
+	bne @2
+	dec SD_ACPTR_LEN+1
+@2:
+	; If new length is 0, try to read next block of data
+
+	ora SD_ACPTR_LEN+1
+	bne @3
+	jsr unit_sd_cmd_READ
+	bcc @3
+	jsr kernalstatus_EOI
+@3:
+	jmp dos_EXIT_CLC
+
+msg_ACPTR_read_FD:
+
+	; Read and return one byte
+
+	jsr FD_ACPTR_helper
+	sta TBTCNT
+	sta REG_A
+
+	; Increment pointer, decrement length
+
+	inc FD_ACPTR_PTR+0
+	bne @1
+	inc FD_ACPTR_PTR+1
+@1:
+	dec FD_ACPTR_LEN+0
+	lda FD_ACPTR_LEN+0
+	cmp #$FF
+	bne @2
+	dec FD_ACPTR_LEN+1
+@2:
+	; If new length is 0, try to read next block of data
+
+	ora FD_ACPTR_LEN+1
+	bne @3
+	jsr unit_fd_cmd_READ
+	bcc @3
+	jsr kernalstatus_EOI
+@3:
+	jmp dos_EXIT_CLC
+
+msg_ACPTR_read_RD:
+
+	; XXX provide implementation
+
+
+msg_ACPTR_fail_no_data:
+
+	; XXX What should be the reaction when trying to read and no data is present?
+
+	sta TBTCNT
+	sta REG_A
+	bra msg_ACPTR_EOI
+
+msg_ACPTR_status:
+
+	ldx IDX2_TALKER
+	jmp (msg_ACPTR_status_vectab, X)
+
+msg_ACPTR_status_SD:                   ; get next byte of status - SD card
+
+	ldx SD_STATUS_IDX
+	inc SD_STATUS_IDX
+	lda SD_STATUS_BUF,x
+	bra msg_ACPTR_status_got
+
+msg_ACPTR_status_FD:                   ; get next byte of status - floppy
+
+	ldx FD_STATUS_IDX
+	inc FD_STATUS_IDX
+	lda FD_STATUS_BUF,x
+	bra msg_ACPTR_status_got
+
+msg_ACPTR_status_RD:                   ; get next byte of status - ram disk
+
+	ldx RD_STATUS_IDX
+	inc RD_STATUS_IDX
+	lda RD_STATUS_BUF,x
+
+	; FALLTROUGH
+
+msg_ACPTR_status_got:
+
+	sta TBTCNT                         ; byte return
+	beq msg_ACPTR_reset_status
+
+	jmp dos_EXIT_CLC_A
+
+msg_ACPTR_fail_no_talker:
+
+	; XXX set error code
+
+	jmp dos_EXIT_SEC
+
+msg_ACPTR_reset_status:
+
+	ldx IDX2_TALKER
+	lda #$00
+	sta PAR_TRACK
+	sta PAR_SECTOR
+	jsr (msg_ACPTR_set_status_vectab, x)
+
+	; FALLTROUGH
+
+msg_ACPTR_EOI:
+
+	jsr kernalstatus_EOI
+	jmp dos_EXIT_CLC
+
+
+; Vector tables for jumps
+
+msg_ACPTR_status_vectab:
+
+	!word msg_ACPTR_status_SD
+	!word msg_ACPTR_status_FD
+	!word msg_ACPTR_status_RD
+
+msg_ACPTR_read_vectab:
+
+	!word msg_ACPTR_read_SD
+	!word msg_ACPTR_read_FD
+	!word msg_ACPTR_read_RD
+
+msg_ACPTR_set_status_vectab:
+
+	!word util_status_SD
+	!word util_status_FD
+	!word util_status_RD