Radio Shack TRS-80 Operation Manual page 103

Computer Graphics Operation Manual
- - - - - - - - - - - TRS-aO
® - - - - - - - - - -
Save graphics display to disk
=
inc X after read ;status
;256 bytes per record
;Get next graphics byte
; and put in buffer
;Set flag: file is open
;counter for X values
;
8~
X values
;75 disk records for entire screen
;init X & Y to zero
;Open file
;Move filespec to DCB
;Error if filespec not given
~F~~~H
HL ;Save registers
DE
BC
IY
HL
INITG
HL,DCBEE ;Zero DCB buffer
DE,DCBEE+l
BC,49
(HL)
,~~H
HL
A,~DH
(HL)
Z,ERROR
DE,DCBEE
44lCH
NZ,BOMB
HL,BUFFER
DE,DCBEE
B,~
442~H
NZ,BOMB
A
(OPNFLG),A
A,~E3H
(STATUS) ,A
A
(X) ,A
(Y) ,A
E,A
D,8~
B,75
HL,BUFFER
C,B
B,~
A, (GRAPH)
(HL)
,A
HL
E
A,E
D
NZ,EGRPH ;Same row?
A
E,A
LD
OUT
XOR
OUT
OUT
LD
LD
LD
LD
LD
LD
IN
LD
INC
INC
LD
CP
JR
XOR
LD
PSECT
PUSH
PUSH
PUSH
PUSH
PUSH
CALL
LD
LD
LD
LD
LDIR
POP
LD
CP
JP
LD
CALL
JP
LD
LD
LD
CALL
JP
XOR
LD
NGRPH
NXTREC
GSAVE
~~l
; GSAVE --
~~2
;
~~3
~~4
~~5
~~6
~~7
~~8
~~9
~l~
~ll
~12
~13
~14
~15
~16
~17
~18
~19
~2~
~2l
~22
~23
~24
~25
~26
~27
~28
~29
;
~3~
~3l
~32
~33
~34
~35
~36
~37
~38
~39
~4~
~4l
~42
~43
~44
~45
~46
~47
~48
~49
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