prodos-drivers/cricket/set.time.s
2019-10-03 21:23:00 -07:00

89 lines
2.0 KiB
ArmAsm

;;; SET.TIME utility for The Cricket!
;;; Prompts for time and sends Cricket "Set Time" sequence.
.setcpu "6502"
.linecont +
.feature string_escapes
.include "apple2.inc"
.include "apple2.mac"
.include "../inc/apple2.inc"
.include "../inc/macros.inc"
.org $2000
.proc main
jsr zstrout
scrcode "\rTime: HH:MM:SS XM\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08"
.byte 0
jsr GETLN2
;; Configure SSC
lda #%00001011 ; no parity/echo/interrupts, RTS low, DTR low
sta COMMAND
lda #%10011110 ; 9600 baud, 8 data bits, 2 stop bits
sta CONTROL
;; Clock Commands
;; Set Time "ST HH:MM:SS:XM"
lda #HI('S')
jsr sendbyte
lda #HI('T')
jsr sendbyte
lda #HI(' ')
jsr sendbyte
ldx #0
loop: lda INPUT_BUFFER,x
jsr sendbyte
inx
cmp #HI($0D) ; = CR
bne loop
rts
.endproc
;; Write byte in A to SSC
.proc sendbyte
pha
: lda STATUS
and #(1 << 4) ; transmit register empty? (bit 4)
beq :- ; nope, keep waiting
pla
sta TDREG
rts
.endproc
;;; ------------------------------------------------------------
;;; Output a high-ascii, null-terminated string.
;;; String immediately follows the JSR.
.proc zstrout
ptr := $A5
pla ; read address from stack
sta ptr
pla
sta ptr+1
bne skip ; always (since data not on ZP)
next: jsr COUT
skip: inc ptr
bne :+
inc ptr+1
: ldy #0
lda (ptr),y
bne next
lda ptr+1 ; restore address to stack
pha
lda ptr
pha
rts
.endproc
;;; ------------------------------------------------------------