HardLabs

CGA Redux

hkzlab·CGA_Redux

CGA Redux PCB layout, top view — open source board by hkzlab

About the CGA Redux PCB

CGA Redux is an open source PCB design by hkzlab, published on GitHub under the CC-BY-NC-4.0 license. It is a 4-layer board measuring 337.6 × 105.7 mm, with 168 components from 51 distinct parts.

Other key parts include the 74S112, 74LS74, 74S86, 74S174 and 74LS04. By type, the board carries 79 capacitors, 69 ICs, 15 resistors, 4 connectors and 1 transistor.

It belongs with the retro computing designs in this gallery.

From the project

The Color Graphics Adapter Redux board is a more or less faithful clone of the original IBM CGA, based on the original schematics

The Color Graphics Adapter (CGA) Redux board is a more or less faithful clone of the original IBM CGA, based on the original schematics.

Since revision 0.2 of this board, You can decide to build it with the "new" or "old" style composite output, giving you slightly different colours.

Have a look HERE for a blog post that discusses the difference in regard to the famous 8088MPH demo!

CGA Redux, from the project README
From the project README

Main components on the CGA Redux

74S11274LS7474S8674S17474LS0474LS1667415374LS39374LS0874S3274LS0074LS13874LS17474LS5174LS3274LS24474S0474S1074S0827C25674LS27374LS374MC684574LS86

CGA Redux bill of materials (BOM)

168 components, 51 distinct parts.

QtyPartRefs
1
74S112
U1
2
74LS74
U2, U11
1
74S86
U3
3
74S174
U4, U5, U101
3
74LS04
U6, U16, U20
3
74LS166
U7, U8, U32
2
74153
U9, U10
1
74LS393
U12
2
74LS08
U13, U41
1
74S32
U14
3
74LS00
U15, U25, U46
3
74LS138
U17, U18, U19
3
74LS174
U21, U39, U40
4
74LS51
U22, U27, U47, U48
2
74LS32
U23, U30
3
74LS244
U24, U36, U67
2
74S04
U26, U29
1
74S10
U28
1
74S08
U31
1
27C256
U33
Show 31 more
QtyPartRefs
2
74LS273
U34, U35
5
74LS374
U37, U58, U59, U60, U61
1
MC6845
U38
2
74LS86
U42, U68
2
74S74
U43, U44
1
74LS151
U45
2
74LS02
U49, U65
8
2118
U50, U51, U52, U53, U54, U55, U56, U57
1
74LS125
U62
1
74LS175
U63
1
74LS164
U64
1
74LS245
U66
1
2N3904
Q1
1
COMPOSITE OUT
J1
1
1X4 BERG
P1
1
1X6 BERG
P2
1
Bus_ISA_8bit
P5
70
100nF
C1, C2, C3, C4, C5, C6, C7, C8 +62
6
47p
C20, C21, C22, C23, C31, C32
3
10uF
C24, C26, C27
1
75
R1
1
20
R4
2
680
R5, R7
1
1k
R6
1
750
R8
4
30
R11, R12, R13, R14
1
130
R17
1
2k
R18
1
3k
R19
1
360
R20
1
0
R90

CGA Redux design files

The KiCad project lives in the hkzlab/CGA_Redux repository on GitHub; these links point at the commit this page was built from.

CGA Redux: common questions

How big is the CGA Redux PCB?

The CGA Redux measures 337.6 × 105.7 mm, has 4 copper layers and is 1.6 mm thick.

How many components are on the CGA Redux?

168 components, from 51 distinct parts. The full bill of materials is listed on this page.

Where can I download the CGA Redux design files?

From the hkzlab/CGA_Redux repository on GitHub, which has the KiCad layout and the schematic; the links under Design files point to each one.

Can I use the CGA Redux design in my own project?

It is published under CC-BY-NC-4.0, which limits how it may be reused; read the license before building on it.

Similar boards