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libbasic64 is now vaguely usable

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More consistent set of macros for interacting, a string-reader,
and better-documented preconditions based on disassemblies
This commit is contained in:
Michael Martin 2014-05-14 22:50:49 -07:00
parent 7ad52695d2
commit 31bff0e414
1 changed files with 89 additions and 14 deletions
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103
platform/libbasic64.oph
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@ -40,21 +40,26 @@
;; FP operators. These are all FAC2 OP FAC1
;; with the result in FAC1.
.alias f_plus $b86a
.alias f_minus $b853
.alias f_times $ba2b
.alias f_div $bb12
.alias f_pow $bf7b
.alias f_and $afe9
.alias f_or $afe6
;; PRECONDITIONS: All of these operations but AND and
;; OR require you to have the contents of $61 in the
;; accumulator. calling one of the ld_fac* routines
;; will do that for you automatically. f_add_op also
;; requires that $6F be set properly; only ld_fac2_mem
;; does this.
.alias f_add_op $b86a
.alias f_subtract_op $b853
.alias f_multiply_op $ba2b
.alias f_divide_op $bb12
.alias f_pow_op $bf7b
.alias f_and_op $afe9
.alias f_or_op $afe6
;; Memory-based FP operations. All are MEM OP FAC1.
;; These seem safer; FAC2 seems to have some slippery
;; invariants in it.
.alias f_add $b867
.alias f_subtract $b850
.alias f_multiply $ba28
.alias f_divide $bb0f
;; These are usually safer than the *_op routines.
.alias f_add_mem $b867
.alias f_subtract_mem $b850
.alias f_multiply_mem $ba28
.alias f_divide_mem $bb0f
;; Useful FP constants that live in the ROM.
;; It's plausible that ld_fac1_a or ld_fac1_s16
@ -100,11 +105,65 @@ _fmvlp: lda _2,x
jsr fac1_to_mem
.macend
.macro print_f
.macro fp_load
`ld_fac1 _1
.macend
.macro fp_store
`st_fac1 _1
.macend
.macro fp_print
`ld_fac1 _1
jsr fac1out
.macend
.macro fp_read
lda #<_1
ldy #>_1
jsr ld_fac1_string
.macend
.macro fp_add
lda #<_1
ldy #>_1
jsr f_add_mem
.macend
.macro fp_subtract
jsr ld_fac2_fac1
`ld_fac1 _1
jsr f_subtract_op
.macend
.macro fp_multiply
lda #<_1
ldy #>_1
jsr f_multiply_mem
.macend
.macro fp_divide
jsr ld_fac2_fac1
`ld_fac1 _1
jsr f_divide_op
.macend
.macro fp_pow
jsr ld_fac2_fac1
`ld_fac1 _1
jsr f_pow_op
.macend
.macro fp_and
`ld_fac2 _1
jsr f_and_op
.macend
.macro fp_or
`ld_fac2 _1
jsr f_or_op
.macend
ld_fac1_ti:
jsr $ffde ; RDTIM
sty $63
@ -131,6 +190,22 @@ fac1_to_mem:
bne -
rts
ld_fac1_string:
ldx $7a
sta $7a
txa
pha
lda $7b
pha
sty $7b
jsr $79
jsr $bcf3
pla
sta $7b
pla
sta $7a
rts
fac1out:
ldy #$00 ; Clean out overflow
sty $68