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Replaced some nop's

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There were some doubled up nop's, so I replaced them with paired pushes and pops, saving 4 bytes and wasting 2-3 extra cycles over the original nop's, so there shouldn't be a problem with not waiting long enough.
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Clanmaster21 2019-10-17 20:12:22 +01:00 committed by GitHub
parent 8926c33ab1
commit a2598a4498
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1 changed files with 4 additions and 8 deletions
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12
kernel/sms/kbd.asm
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@ -19,8 +19,7 @@ smskbdFetchKCA:
; Port A TH output, low
ld a, 0b11011101
out (0x3f), a
nop
nop
push hl ; nop, pairs with a pop later
in a, (0xdc)
; bit 3:0 are our dest bits 3:0. handy...
and 0b00001111
@ -28,8 +27,7 @@ smskbdFetchKCA:
; Port A TH output, high
ld a, 0b11111101
out (0x3f), a
nop
nop
pop hl ; nop, and matches with push
in a, (0xdc)
; bit 3:0 are our dest bits 7:4
rlca \ rlca \ rlca \ rlca
@ -59,8 +57,7 @@ smskbdFetchKCB:
; Port B TH output, low
ld a, 0b01110111
out (0x3f), a
nop
nop
push hl ; nop, matches with pop later
in a, (0xdc)
; bit 7:6 are our dest bits 1:0
rlca \ rlca
@ -75,8 +72,7 @@ smskbdFetchKCB:
; Port B TH output, high
ld a, 0b11110111
out (0x3f), a
nop
nop
pop hl ; nop, matches earlier push
in a, (0xdc)
; bit 7:6 are our dest bits 5:4
rrca \ rrca