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Gidubba
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Work on the infrastructure for copying, and ignore leader when reading a tape and stop reading at trailer or empty reader

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CrazyEttin 2022-08-19 22:27:45 +03:00
parent 955992988c
commit 62329e91d1
1 changed files with 132 additions and 7 deletions
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139
gidubba.asm
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@ -335,10 +335,123 @@ setmrk: load r0, target
;***
;Copy to mark
;Copy to mark (under construction)
;Placeholder
copy: breq r0, r0, cmdp
;Find the argument line in the save and store its number
copy: cleq r0, r0, fend
;Get the save address of the line
;High byte
load r0, sublod + 1
store test1 + 1, r0
store testa + 1, r0
;Low byte
load r0, sublod + 2
store test1 + 2, r0
store testa + 2, r0
;Check for the save end
testa: load r0, 0
load r1, sub
breq r0, r1, cmdp
;Restore the buffer start address
;High byte
load r0, bfstrt
store test2 + 1, r0
;Low byte
load r0, bfstrt + 1
store test2 + 2, r0
;Initialise the character counter
xor r0, r0
;Read a character
test1: load r1, 0
;Check for save and buffer ends
;Save end
load r2, sub
breq r1, r2, test3
;Buffer end
load r2, bfsize
breq r0, r2, test3
;Store the character in the buffer
test2: store 0, r1
;Check for line and save ends
;Line end
load r2, lf
breq r1, r2, test4
;Increment the character counter and store it in r3
;Increment
load r2, const1
cleq r0, r0, sum
;Store
xor r3, r3
xor r3, r0
;Increment the save address
;Low byte
load r0, test1 + 2
load r2, const1
cleq r0, r0, sum
store test1 + 2, r0
;Add the overflow to the high byte
load r0, test1 + 1
xor r2, r2
xor r2, r1
cleq r0, r0, sum
store test1 + 1, r0
;Increment the buffer address
;Low byte
load r0, test2 + 2
load r2, const1
cleq r0, r0, sum
store test2 + 2, r0
;Add the overflow to the high byte
load r0, test2 + 1
xor r2, r2
xor r2, r1
cleq r0, r0, sum
store test2 + 1, r0
;Reload the character counter to r0
xor r0, r0
xor r0, r3
;Read the next character
breq r0, r0, test1
;Force line end
test3: load r1, test2 + 1
store test5 ,r1
load r1, test2 + 2
store test5 ,r1
;Store the CR of a newline in the buffer
load r0, cr
test5: store 0, r0
;Increment the buffer address
;Load the address
load r0, test2 + 1
load r1, test2 + 2
;Increment
cleq r0, r0, incdw
;Store the address
store test6 + 1, r0
store test6 + 2, r1
;Store the LF of a newline in the buffer
load r0, lf
test6: store 0, r0
;Return to the command prompt
test4: breq r0, r0, cmdp
;***
@ -529,7 +642,7 @@ print: load r0, cstff
;***
;Write the text to tape
;Write the text to the tape punch
;Get the tape punch address
;High byte
@ -551,7 +664,7 @@ write: load r0, cstff
;***
;Read the text from tape
;Read the text from the tape reader
;Get the save start address
;High byte
@ -561,11 +674,23 @@ read: load r0, svstrt
load r0, svstrt + 1
store chrsto + 2, r0
;Ignore the leader
iglead: load r1, fffd
xor r2, r2
breq r1, r2, iglead
breq r0, r0, chkend
;Read a character
chread: load r1, fffd
;Check for empty tape reader
xor r2, r2
;Check for trailer or empty tape reader
;Trailer
chkend: xor r2, r2
brneq r1, r2, chkntp
load r1, sub
breq r0, r0, chrsto
;Empty tape reader
chkntp: nand r2, r2
brneq r1, r2, chrsto
load r1, sub