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This commit is contained in:
Phil Budne
2016-03-25 18:02:59 -04:00
parent 5567d705d5
commit cb3104a8a8
1 changed files with 34 additions and 34 deletions
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68
src/cmd/ed1.s
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@@ -555,13 +555,13 @@ gline: 0
tad otal
jmp i gline
rline: 0
rline: 0 " read line from stdin
lac linep
dac tal
1:
cla
sys read; char; 1 " read a char or two
sys read; char; 1 " read a char (or two)
lac char
"** 08-rest.pdf page 17
"[handwritten page number top right of scan - 10]
@@ -609,47 +609,47 @@ esc: 0 " edit/save char
dac linsiz
jmp i rline " return from rline
getsc: 0
lac i getsc
getsc: 0 " call: jms getsc; pbufp
lac i getsc " fetch buffer pointer addr from after call
dac sctalp
isz getsc
lac i sctalp
isz getsc " skip buffer pointer pointer
lac i sctalp " fetch buffer pointer
dac sctal
add o400000
dac i sctalp
ral
lac i sctal
szl
lrss 9
and o777
add o400000 " flip high bit (carry wraps around)
dac i sctalp " save pointer back
ral " shift high bit into link
lac i sctal " fetch word from buffer
szl " link set?
lrss 9 " yes: shift high char down
and o777 " mask to character
jmp i getsc
putsc: 0
and o777
putsc: 0 " call: jms putsc; pbufp
and o777 " mask to single 9-bit character
"** 08-rest.pdf page 18
"[handwritten page number top right of scan - 11]
lmq
lac i putsc
lmq " put in MQ
lac i putsc " fetch buffer pointer pointer
dac sctalp
isz putsc
lac i sctalp
dac sctal
add o400000
dac i sctalp
sma cla
jmp 1f
llss 27
dac i sctal
lrss 9
jmp i putsc
isz putsc " skip over pointer pointer
lac i sctalp " get pointer
dac sctal " save it for later
add o400000 " flip high bit, wrap carry
dac i sctalp " save back as buffer pointer pointer
sma cla " high bit set?
jmp 1f " no
llss 27 " yes: get MQ in high half of AC
dac i sctal " save to buffer
lrss 9 " shift char back down
jmp i putsc " return
1:
lac i sctal
and o777000
omq
dac i sctal
lacq
jmp i putsc
lac i sctal " get word from buffer
and o777000 " mask to high character
omq " OR in new char
dac i sctal " save word
lacq " restore char
jmp i putsc " return
append: 0
-1