Added eightballvmzp_a2e.S, which was missed for v0.75

This commit is contained in:
Bobbi Webber-Manners 2018-06-02 23:53:32 -04:00
parent da7dea8906
commit d0cf5fc223
1 changed files with 18 additions and 0 deletions

18
eightballvmzp_a2e.S Normal file
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;
; Apple II zero page is used for VM
; registers: evalptr, PC, SP, FP
; $80-$9a are used by cc65 ZP segment so avoid this range
; Zero-page usage is documented in:
; ProDOS 8 Technical Reference Manual Section A.4
; The upper half of ZP is generally used by BASIC only, so we can use it.
.exportzp _evalptr := $a0
.exportzp _pc := $a1
.exportzp _sp := $a3
.exportzp _fp := $a5
.exportzp _wordptr := $a7
.exportzp _byteptr := $a9
.exportzp _evalstack := $ab ; 32 bytes