avra: code consolidation

This commit is contained in:
Virgil Dupras 2019-12-15 19:17:03 -05:00
parent 52359a4e42
commit b130cac635

View File

@ -160,8 +160,8 @@ instrTbl:
.db 0x04, 0b01100000, 0x00 ; SBR
.db 0x04, 0b01010000, 0x00 ; SUBI
; k(12): XXXXkkkk kkkkkkkk
.db 0x00, 0b11010000, 0x00 ; RCALL
.db 0x00, 0b11000000, 0x00 ; RJMP
.db 0x08, 0b11010000, 0x00 ; RCALL k
.db 0x08, 0b11000000, 0x00 ; RJMP k
; IN and OUT
.db 0x07, 0b10110000, 0x00 ; IN
.db 0x87, 0b10111000, 0x00 ; OUT (Bit 7)
@ -298,7 +298,7 @@ parseInstruction:
cp I_RCALL
jr c, .spitRdK8
cp I_IN
jr c, .spitK12
jr c, .spitk12
cp I_BREAK
jp c, .spitINOUT
cp I_ASR
@ -319,13 +319,8 @@ parseInstruction:
rr b ; K(8) start at B's 1st bit, not 2nd
jr .spit
.spitK12:
; Let's deal with the upcode constant before we destroy IX below
ld b, (ix+1)
call readWord
call parseExpr
ret nz
push ix \ pop hl
.spitk12:
; k(12) in HL
; We're doing the same dance as in _readk7. See comments there.
ld de, 0xfff
add hl, de
@ -341,12 +336,12 @@ parseInstruction:
; We're within bounds! Now, divide by 2
ld a, l
rr h \ rra
; LSB in A, spit
call ioPutB
; LSB in A
ld c, a
ld a, h
and 0xf
or b
jp ioPutB
ld b, a
jr .spit
.spitINOUT:
; Rd in H, A in L
@ -473,6 +468,7 @@ parseInstruction:
; 'a' - A 5-bit I/O port value
; 'A' - A 6-bit I/O port value
; 'b' - a 0-7 bit value
; 'D' - A double-length number which will fill whole HL.
; 'R' - an r5 value: r0-r31
; 'r' - an r4 value: r16-r31
;
@ -488,6 +484,7 @@ argSpecs:
.db 'R', 'b' ; Rd(5) + bit
.db 'b', 7 ; bit + k(7)
.db 'R', 'A' ; Rd(5) + A(6)
.db 'D', 0 ; K(12)
; Parse arguments from I/O according to specs in HL
; H for first spec, L for second spec
@ -540,6 +537,8 @@ _parseArgs:
jr z, _readk7
cp 8
jr z, _readK8
cp 'D'
jr z, _readDouble
ret ; something's wrong
; Read expr and return success only if result in under number given in A
@ -572,6 +571,17 @@ _readK8:
ld a, 0xff
jr _readExpr
_readDouble:
push ix
call parseExpr
jr nz, .end
push ix \ pop hl
; HL is already set. For good measure, let's set A to HL's MSB
ld a, h
.end:
pop ix
ret
_readk7:
push hl
push de