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adapted to Kick Assembler, some documentation update

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FeralChild64 committed 2019-09-07 12:35:21 +02:00
1 parent ae23dbae7b
commit de27124b4f
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+4181 -3976
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c64/kernal/ciout.s
+14 -14
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@@ -1,37 +1,37 @@
;;
;; Official Kernal routine, described in:
;;
;; - [RG64] C64 Programmer's Reference Guide - page 279/280
;; - [CM64] Compute's Mapping the Commodore 64 - page 224
;;
;; CPU registers that has to be preserved (see [RG64]): .X, .Y
;;
//
// Official Kernal routine, described in:
//
// - [RG64] C64 Programmer's Reference Guide - page 279/280
// - [CM64] Compute's Mapping the Commodore 64 - page 224
//
// CPU registers that has to be preserved (see [RG64]): .X, .Y
//
ciout:
CIOUT:
pha
lda C3PO
bne ciout_send_byte
;; Nothing to send - set buffer as valid, store byte there
// Nothing to send - set buffer as valid, store byte there
inc C3PO
;; Clear carry flag to indicate success
// Clear carry flag to indicate success
clc
ciout_store_in_buffer:
;; Store in the buffer data to be sent next, return
// Store in the buffer data to be sent next, return
pla
sta BSOUR
rts
ciout_send_byte:
clc ; don't send with EOI
clc // don't send with EOI
jsr iec_tx_byte
inc C3PO ; iec_tx_byte sets it to 0, but we still have something to send
inc C3PO // iec_tx_byte sets it to 0, but we still have something to send
jmp ciout_store_in_buffer