HardLabs

Main board

nojan1·project-wrass·eda/main-board/main-board.kicad_pcb

Main board layout, top view — open source board by nojan1

About the Main board

Main board is an open source PCB design by nojan1, published on GitHub. It is a 4-layer board measuring 230 × 100 mm, with 74 components from 33 distinct parts.

Other key parts include the W65C02SxP, NA555P, 28C256, AS6C4008-55PCN and 74HCT138. By type, the board carries 23 capacitors, 19 ICs, 14 diodes, 10 resistors, 7 connectors and 1 crystal.

From the project

The purpose of Project Wrass is to develop the Wrass 1.

The purpose of Project Wrass is to develop the Wrass 1.

A 6502 based computer having the following specs.

W65C02 running at 2Mhz Bankable RAM giving a total of approx 300KB of usable memory * Expansion bus for up to 16 devices

The 16KB ROM is bankable using an external switch. This allows the computer to run "2 sets" of software.

The existing one is a simple homebrew "monitor" giving access to simple read, write and jump commands.

Main board, from the project README
From the project README

Main components on the Main board

W65C02SxPNA555P28C256AS6C4008-55PCN74HCT13874HCT3274HCT0874HCT3074HCT13974HCT0074HCT24574LHCT15774HCT27374HCT541

Main board bill of materials (BOM)

74 components, 33 distinct parts.

QtyPartRefs
1
W65C02SxP
U1
1
NA555P
U2
1
28C256
U3
1
AS6C4008-55PCN
U4
2
74HCT138
U5, U13
2
74HCT32
U6, U12
1
74HCT08
U7
1
74HCT30
U8
1
74HCT139
U9
1
74HCT00
U10
1
74HCT245
U11
2
74LHCT157
U14, U15
1
74HCT273
U16
3
74HCT541
U17, U18, U20
1
4Mhz
X1
1
RomHighSel
J1
1
Membank block
J2
1
ResetSwitch
J3
1
$1-3 latch
J4
1
PWR
J5
Show 13 more
QtyPartRefs
1
CS_leds
J6
1
Expansion
J7
13
1N4007
D1, D2, D3, D4, D5, D6, D7, D8 +5
1
LED
D14
1
10n
C1
1
10u
C2
19
100n
C3, C4, C7, C8, C9, C10, C11, C12 +11
1
1u
C5
1
3u
C6
1
47k
R1
1
1M
R2
6
10k
R3, R4, R6, R7, R8, R9
2
1k
R5, R10

Main board design files

The KiCad project lives in the nojan1/project-wrass repository on GitHub; these links point at the commit this page was built from.

Main board: common questions

How big is the Main board?

The Main board measures 230 × 100 mm, has 4 copper layers and is 1.6 mm thick.

How many components are on the Main board?

74 components, from 33 distinct parts. The full bill of materials is listed on this page.

Where can I download the Main board design files?

From the nojan1/project-wrass repository on GitHub, which has the KiCad layout and the schematic; the links under Design files point to each one.

Can I use the Main board design in my own project?

The repository has no license, so all rights stay with nojan1. Use it as a reference, and ask the author before reusing the design.

More boards in project-wrass