Chromatics CG-1599

Early 1980s Graphics Display System

     See the description of the CG series on the Chromatics Wikipedia page.  This system includes the CRT, logic chassis filled with cards, light pen, dual 8” floppy drives, Maxi-Switch keyboard, and EECO paper tape reader.  There are no floppy disks or paper tapes, or manuals although Bitsavers has a couple of documents that are copied here for convenience.  There ARE however some EPROMs that appear to contain boot code as well as Microsoft BASIC customized for this system.  These EPROMs have been imaged and are linked below.  Google AI was used to analyze these EPROMs (link below), but as a raw AI product I don’t know if it is complete nonsense so it needs to be vetted for accuracy and meaning.

     This system has not been powered on in decades.  It has small tantalum teardrop capacitors everywhere that are being replaced, as are the electrolytics.  The power relay in the back of the logic chassis tested bad and was replaced.  The large Sprague orange drop cap connected to the relay has also been replaced with a 0.1uF X2 filter cap.

CRT Details
Logic Chassis Details
Keyboard Details
Power Supply Details
Paper Tape Reader Details
Dual 8” Floppy Drive Details
Light Pen Details
EPROMs/PROMs (here is a zip file with all of the 2716s plus all the bipolar PROMs but missing UG5, UE8 on CPU)
Board
Location
Label
Type
SVI
UE1
210095
Intersil 5623
UH2
210075
Signetics 82S129
UF2
210096
82S129
UA2
210090
TI TMS2716
PROM Expander
UC2
210080  2000H  V3.5
2716
UD2
SVI 2800H V3.3
2716
UE1
210011
TI TBP18S22
UE2
3000H V3.3
2716
UE3
210012
18S22
Light Pen/SIO 2 & 3
UH1
210047
TI 74S471
UH2
210048
82S129
‘181 board (100234)
UA4
210081
18S22
UA5
210084
18S22
UB4
210082
18S22
UC4
210083
18S22
UF5
210085
82S129
CPU
UD6
Bartlett 0000H Ver 3.5
2716
UE6
210078  0800H V 3.5 XX99
2716
UF6
210079 V 3.5 1000H
2716
UG6
11/80  12
2716
UG5
210017
18S22
UE8
210018
18S22
64K RAM (2 boards)
UC1
210009
18S22
UD1
210010
18S22
UE1
210010
18S22
UG1
210009
18S22
XX99 Memory
UA2
210006
5623
UA3
210002
5623
UA4
210002
5623
UB2
210001
5623
UB3
210002
5623
UB4
210002
5623
UB5
?
18S22
UC3
210002
5623
UC4
210002
5623
UD3
210002
5623
UD4
210002
5623
UD6
210005
5623
UH6
210055
18S22
Buffer Memory
UH6
210031  C000H BASIC Ver 3.0
2716
UG6
210032  C800H Ver 3.1
2716
UE6
210033  D000H Ver 3.0
2716
UC6
210034  D800H Ver 3.0
2716
UH5
210054  E000H Ver 3.1
2716
UG5
210036  E800H Ver 3.0
2716
UE5
210037  F000H Ver 3.0
2716
UC5
210038  F800H Ver 3.0
2716
UE4
CR07 or LR07?
74S287
Keyboard
U6
022
74S287
U7
023
74S287
U8
021
74S287
Waveform Generator
U5
220015
74S287
Individual 2716 dumps:
Google AI Analysis