Radio Shack TRS-80 - Page 106

Operation Manual
Computer Graphics
----------TRS-BO ® ----------
Save graphics display to disk
:256 bytes per record
:Open file
:Move filespec to DCB
:status = inc X after write
:Read record from disk
:Set flag: file is open
:counter for X values
:8.0 X values
:75 disk records for entire screen
:init X & Y to zero
HL
A,.0DH
(HL)
Z,ERROR
DE,DCBEE
441CH
NZ,BOMB
HL,BUFFER
DE,
DCBEE
B,.0
4424H
NZ,BOMB
A
(OPNFLG) ,A
A,.0B3H
(STATUS) ,A
A
(X) ,A
(Y) ,A
E,A
D,8.0
B,75
DE
DE,DCBEE
4436H
DE
NZ,BOMB
HL,BUFFER
C,B
B,.0
A, (HL)
(GRAPH) ,A
HL
E
.0F.0.0.0H
HL :Save registers
DE
BC
IY
HL
INITG
HL,DCBEE
:Zero DCB buffer
DE,DCBEE+l
BC,49
(HL) ,H
LD
OUT
XOR
OUT
OUT
LD
LD
LD
PUSH
LD
CALL
POP
JR
LD
LD
LD
LD
OUT
INC
INC
PSECT
PUSH
PUSH
PUSH
PUSH
PUSH
CALL
LD
LD
LD
LD
LDIR
POP
LD
CP
JR
LD
CALL
JR
LD
LD
LD
CALL
JP
XOR
LD
NXTREC
NGRPH
GLOAD
.0.01 : GLOAD --
.0.02 :
.0.03
.0.04
.0.05
.0.06
.0.07
.0.08
.0.09
.01.0
.011
.012
.013
.014
.015
.016
.017
.018
.019
.02.0
.021
.022
.023
.024
.025
.026
.027
.028
.029 :
.03.0
.031
.032
.033
.034
.035
.036
.037
.038
.039
.04.0
.041
.042
.043
.044
.045
.046
.047
.048
.049
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