6 layers244 × 244 mm
Retroslop
CPTforever/8088-MicroATX-Computer
A 8088 based, IBM 5150 like computer compatible with the MicroATX motherboard form factor.
193 parts
4 layers
Mb68k
ziggekatten/m68kA over ambitious project to build a usable computer from scratch
- Copper layers
- 4
- Thickness
- 1.6 mm
- Parts
- 130
- Nets
- 280
- Pads
- 870
- Tracks, vias
- 0, 0
- Routed
- Not yet
- KiCad
- KiCad 7 (file 20221018)
- Created
- 31 Jan 2022
- Updated
- 29 Jan 2024
Overview
Mb68k is an open-source printed circuit board by ziggekatten, from the ziggekatten/m68k repository on GitHub, published under the MIT licence. It is a 4-layer board with 130 parts on 280 nets.
It is built around the 74LS245SC, AS6C4008-55PCN and 74LS05P-E, with the 74LS175PC and NE555P among its other parts. Its parts include 40 resistors, 28 capacitors, 23 connectors, 20 ICs and 16 diodes. It belongs with the FPGA and CPLD boards of this library.
Main components
574LS245SC
-0℃~+70℃ 12ns@5V,45pF 15mA 24mA 4.75V~5.25V 74LS 8 Bidirectional Output enable Schmitt trigger Tri-State - Buffers, Drivers, Receivers, Transceivers ROHSTexas InstrumentsBuffers, Drivers, Receivers, Transceivers
AS6C4008-55PCN
PDIP-320℃~+70℃ 2.7V~5.5V 30mA 4Mbit 4uA 55ns Parallel Port (Parallel) PDIP-32 SRAM ROHSAlliance MemorySRAM74LS05P-E
-- Inverters ROHSRenesas ElectronicsLogic Gates
74LS175PC
PDIP-160℃~+70℃ 1 10ns 18mA 25ns@5V,15pF 30MHz 4 4.75V~5.25V 5ns 74LS Series Asynchronous Complementary type D-Type Reset Rising Edge PDIP-16 Flip Flops ROHSTexas InstrumentsFlip Flops
NE555P
DIP-80℃~+70℃ 100kHz 10mA 4.5V~16V DIP-8 555 Timers / Counters ROHSTexas InstrumentsTimers / Counters
README
kicad/README.mdHardware design
Basic principles:
- Use of buffers when in doubt. The 68010 pins can't drive that much current
TODO: description
- CPU: MC68010@12MHz
- DUART: MC68681
- 2 * 512K FLASH ROM
- 2 x 512K SRAM
Memory map
TODO: description
| Start address (hex) | End address (hex) | Usage |
|---|---|---|
| 0x00100000 | 0x00200000 | Onboard RAM |
| 0x00000000 | 0x00100000 | Onboard ROM |
Parts
130| Qty | Value | Footprint | References |
|---|---|---|---|
| 24 | 100nF | Capacitor_THT:CP_Radial_D5.0mm_P2.50mm | C1, C10, C11, C12, C13, C14, C15, C16, C17, C18, C21, C22, C23, C24, C26, C27 +8 |
| 19 | 4k7 | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R10, R11, R12, R13, R14, R15, R16, R31, R32, R33, R34, R35, R36, R37, R38, R39 +3 |
| 14 | R330 | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R17, R18, R19, R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30 |
| 8 | Free pin | Connector_PinSocket_2.54mm:PinSocket_1x01_P2.54mm_Vertical | J9, J10, J14, J15, J16, J17, J18, J19 |
| 5 | 74LS244 | Package_DIP:DIP-20_W7.62mm_Socket | U3, U8, U9, U18, U19 |
| 4 | Conn_01x01_Pin | Connector_PinSocket_2.54mm:PinSocket_1x01_P2.54mm_Vertical | J1, J3, J4, J5 |
| 4 | GAL22V10 | Package_DIP:DIP-24_W7.62mm_Socket | U4, U10, U16, U17 |
| 3 | 4K7 | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R1, R2, R6 |
| 2 | 330R | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R3, R4 |
| 2 | 74LS245 | Package_DIP:DIP-20_W7.62mm_Socket | U13, U14 |
| 2 | 7pF | Capacitor_THT:CP_Radial_D5.0mm_P2.50mm | C19, C20 |
| 2 | AS6C4008-55PCN | Package_DIP:DIP-32_W15.24mm_Socket | U11, U12 |
| 2 | SST39SF040 | Package_DIP:DIP-32_W15.24mm_Socket | U5, U6 |
| 2 | Spare resistors | Connector_PinSocket_2.54mm:PinSocket_1x10_P2.54mm_Vertical | J20, J22 |
| 1 | 100uF | Capacitor_THT:CP_Radial_D5.0mm_P2.50mm | C2 |
| 1 | 10uF | Capacitor_THT:CP_Radial_D5.0mm_P2.50mm | C25 |
| 1 | 270R | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R7 |
| 1 | 2K2 | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R5 |
| 1 | 68010P10 | Package_DIP:DIL64 | U7 |
| 1 | 68681 | Package_DIP:DIP-40_W15.24mm_Socket | U15 |
| 1 | 74LS05 | Package_DIP:DIP-14_W7.62mm | U1 |
| 1 | 74LS175 | Package_DIP:DIP-16_W7.62mm_Socket | U20 |
| 1 | BUS Slot #1 | Connector_PinSocket_2.54mm:PinSocket_2x40_P2.54mm_Vertical | J23 |
| 1 | Conn_01x06_Pin | Connector_PinSocket_2.54mm:PinSocket_1x06_P2.54mm_Vertical | J2 |
| 1 | Crystal | Crystal:Crystal_HC18-U_Vertical | 3.6864MHz1 |
| 1 | DUART I/O | Connector_PinSocket_2.54mm:PinSocket_1x20_P2.54mm_Vertical | J8 |
| 1 | DUARTA_RX | LED_THT:LED_D5.0mm | D11 |
| 1 | DUARTA_TX | LED_THT:LED_D5.0mm | D12 |
| 1 | DUARTB_RX | LED_THT:LED_D5.0mm | D13 |
| 1 | DUARTB_TX | LED_THT:LED_D5.0mm | D14 |
| 1 | FC1 | LED_THT:LED_D5.0mm | D8 |
| 1 | FC2 | LED_THT:LED_D5.0mm | D9 |
| 1 | FC3 | LED_THT:LED_D5.0mm | D10 |
| 1 | Free Pins | Connector_PinSocket_2.54mm:PinSocket_1x05_P2.54mm_Vertical | J11 |
| 1 | Free pins | Connector_PinSocket_2.54mm:PinSocket_1x03_P2.54mm_Vertical | J13 |
| 1 | Free pins | Connector_PinSocket_2.54mm:PinSocket_1x06_P2.54mm_Vertical | J12 |
| 1 | GREEN Run | LED_THT:LED_D5.0mm | LED2 |
| 1 | HW_RESET_SW | Button_Switch_SMD:SW_MEC_5GSH9 | SW1 |
| 1 | IRQ1 | LED_THT:LED_D5.0mm | D1 |
| 1 | IRQ2 | LED_THT:LED_D5.0mm | D2 |
| 1 | IRQ3 | LED_THT:LED_D5.0mm | D3 |
| 1 | IRQ4 | LED_THT:LED_D5.0mm | D4 |
| 1 | IRQ5 | LED_THT:LED_D5.0mm | D5 |
| 1 | IRQ6 | LED_THT:LED_D5.0mm | D6 |
| 1 | IRQ7 | LED_THT:LED_D5.0mm | D7 |
| 1 | NE555P | Package_DIP:DIP-8_W7.62mm | U2 |
| 1 | PORTA serial | Connector_PinSocket_2.54mm:PinSocket_1x06_P2.54mm_Vertical | J6 |
| 1 | PORTB serial | Connector_PinSocket_2.54mm:PinSocket_1x06_P2.54mm_Vertical | J7 |
| 1 | Power bar | Connector_PinSocket_2.54mm:PinSocket_2x11_P2.54mm_Vertical | J21 |
| 1 | RED Reset | LED_THT:LED_D5.0mm | LED1 |
| 1 | SG-8002DB 10Mhz | Oscillator:Oscillator_DIP-14 | X1 |
Questions
What parts does the Mb68k use?
130 parts, built around the 74LS245SC, AS6C4008-55PCN, 74LS05P-E and 74LS175PC. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Mb68k KiCad files?
From the ziggekatten/m68k repository on GitHub, at the commit this page was made from: the board is kicad/mb68k.kicad_pcb and its schematic kicad/CPU.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Mb68k design in my own project?
Its repository publishes it under the MIT licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
Similar boards
- 4 layers253.6 × 137.7 mm
S100 Thunder186-1.0-006
RichCini/LomasBoards
Small repository of files/data related to Lomas Data Products S-100 boards.
118 parts1 - 4 layers340 × 210 mm
- 4 layers171.5 × 171.6 mm
- 2 layers478 × 183 mm
- 2 layers143.3 × 77.5 mm
Pedisk
mnaberez/pedisk2
Reverse engineering the CGRS Microtech PEDISK II disk system for Commodore PET/CBM computers
43 parts3 - 2 layers100 × 77.5 mm
- 2 layers
CompaqportableIII
raymondh2/CompaqPortableIII
Current PCB Memory Expansion board layout is untested. The backplane for the expansion cards is tested and working.
123 parts17