Basic Program; Servicing Diagrams; Basic Color Bar Program - Zenith ZVM-131 Service Manual

3. The hand prompt will continue to be seen at the bot-
tom of the color bar.
4. When the necessary adjustments have been made,
press the DELETE key to return to the test menu.
BASIC PROGRAM
The program in Listing 1 can be used to produce a color
bar pattem on a Z-100 with the color option.
1. Turn on the computer.
2. Boot Z-DOS and start Z-BASIC.
3. Enter and run the BASIC program in Listing 1.
Listing 1. BASIC Color Bar Program
10 REM clear screen
20 CLS
30 REM produce color bar
40 LlNE(0,0)-(79,106),O,BF
50 LlNE(80,O)-(1S9,1 06),1 ,BF
60 LlNE(160,O)-(239,106),4,BF
70 LlNE(240,O)-(319,1 06),S,BF
80 LlNE(320,0)-(399,1 06),2,BF
90 LlNE(400,0)-(479,1 06),3,BF
100 LlNE(480,0)-(S99,1 06),6,BF
110 LlNE(S60,0)-(639,1 06), 7,BF
120 REM label bars
130 LOCATE 13,S
140 PRINT TAB(S);"BLACK";
TAB(1S) ;"BLUE";TAB(2S);"RED";
1S0 PRINT TAB(3S);"MAGENTA";
TAB(4S) ;"GREEN";TAB(SS) ;"CYAN";
160 PRINT TAB(6S);"YELLOW";TAB(7S);"WHITE"
170 REM end of program
180 END
Servicing
Servicing Diagrams
Use the following block diagrams to locate schematics
while tracing signal and power circuits during troubleshoot-
ing.
Waveform representations are provided with adjacent
schematic and component location drawings. The source
location of waveforms are shown on both schematic and
component location drawing.
A Zenith Z-160 computer was used to supply the RGB and
composite signals for generating the waveforms.
NOTE: Some of the input and output waveforms that are
shown were taken from the adjacent boards because mon-
itor points were more accessable there. Therefore, look for
input and output waveforms for the interfacing boards of
the board being troubleshot.
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