2 layers55.2 × 23.5 mm
4 layers158.8 × 104.1 mm
8-Bit CPU
frenchie/8-Bit-Computer20An 8-Bit Computer
- Size
- 158.8 × 104.1 mm
- Copper layers
- 4
- Thickness
- 1.6 mm
- Parts
- 323
- Nets
- 404
- Pads
- 1,669
- Tracks, vias
- 4,822, 752
- Pours
- 2
- Routed
- Yes
- KiCad
- KiCad 5 (file 20171130)
- Created
- 23 Aug 2019
- Updated
- 2 Aug 2020
Overview
8-Bit CPU is an open-source printed circuit board by frenchie, from the frenchie/8-Bit-Computer repository on GitHub. It is a 4-layer board of 158.8 × 104.1 mm with 323 parts on 404 nets, routed with 4,822 tracks and 752 vias.
It is built around the ATMEGA16-16AU, ATMEGA48-20AU and ATTINY45-20SU, with the 74HC245D, K7805M-1000R3 and 74HC1G00GW among its other parts. Its parts include 107 diodes, 64 capacitors, 53 ICs, 47 resistors and 8 switches. It belongs with the retro computing and games boards and the AVR (ATmega, ATtiny) boards of this library.
Main components
12
ATMEGA16-16AU
TQFP-44(10x10)-40℃~+85℃ 10bit 16KB 16MHz 1KB 32 4.5V~5.5V 512Byte 8 Bit AVR Built-in FLASH TQFP-44(10x10) Microcontrollers (MCU/MPU/SOC) ROHSMicrochip TechnologyMicrocontrollers (MCU/MPU/SOC)
ATMEGA48-20AU
TQFP-32(7x7)-40℃~+85℃ 10bit 2.7V~5.5V 20MHz 23 256Byte 4KB 512Byte 8 Bit AVR Built-in FLASH TQFP-32(7x7) Microcontrollers (MCU/MPU/SOC) ROHSMicrochip TechnologyMicrocontrollers (MCU/MPU/SOC)
ATTINY45-20SU
SOIC-8-208mil-40℃~+85℃ 10bit 2.7V~5.5V 20MHz 256Byte 256Byte 4KB 6 8 Bit AVR Built-in FLASH SOIC-8-208mil Microcontrollers (MCU/MPU/SOC) ROHSMicrochip TechnologyMicrocontrollers (MCU/MPU/SOC)
74HC245D
SO-20-300mil-40℃~+125℃ 1 160uA 2V~6V 7.8mA 7.8mA 74HC 8 9ns@4.5V,50pF Bidirectional Tri-State SOIC-20-300mil Buffers, Drivers, Receivers, Transceivers ROHSNexperiaBuffers, Drivers, Receivers, Transceivers
K7805M-1000R3
SIP-3-40℃~+85℃ 1 10.4mm 11.6mm 1A 2200uF 25mVp-p 300uA、1mA 520kHz 5V 7V~36V 8mm 94% Buck-Boost Short Circuit Protection ±3% SIP-3 DC-DC Power Modules ROHSYLPTECDC-DC Power Modules
74HC1G00GW
SOT-353-40℃~+125℃ 1 1.5V~4.2V 1.9V、4.13V、5.63V 100mV、330mV 2 2.6mA 2.6mA 20uA 23ns@6V,50pF 2V~6V 500mV~1.8V 74HC Series NAND Gate SOT-353 Logic Gates ROHSNexperiaLogic Gates74HC377D
SO-20-300mil-40℃~+125℃ 1 12ns 16ns@4.5V,50pF 2V~6V 3.5pF 3ns 4mA 4mA 74HC Series 77MHz 8 8uA D-Type Enable Rising Edge SOIC-20-300mil Flip Flops ROHSNexperiaFlip Flops
74HC1G32GV
SOT-23-5-40℃~+85℃ 1 1.5V、3.15V、4.2V 1.9V、4.4V、5.9V 100mV、260mV、330mV 10uA 2 2.6mA 2.6mA 21ns@6V,50pF 2V~6V 500mV、1.35V、1.8V 74HC OR Gate SOT-23-5 Logic Gates ROHSTECH PUBLICLogic Gates
74HC161S
SOP-160℃~+70℃ 20MHz 2V~6V 4 500mW Asynchronous Hexadecimal Counter Rising Edge Synchronous Up Counter SOP-16 Counters, Dividers ROHSGRCounters, Dividers
74HC157D
SO-16-40℃~+125℃ 10ns@6.0V,50pF 160uA 2V~6V 5.2mA 5.2mA 74HC 8/4 Multiplexer Single Supply SOIC-16 Signal Switches, Multiplexers, Decoders ROHSNexperiaSignal Switches / Encoders & Decoders / Multiplexers74HC1G08GW
SOT-353-40℃~+125℃ 1 1.5V~4.2V 100mV、400mV 2 2.6mA 2.6mA 20uA 23ns@6V,50pF 2V~6V 5.2V、5.9V~6V 500mV~1.8V 74HC Series AND Gate SOT-353 Logic Gates ROHSNexperiaLogic Gates
74HC00D
SOP-14-40℃~+125℃ 1.5V、3.15V、4.2V 1.9V、3.7V、5.9V 100mV、400mV、400mV 2 2V~6V 4 40uA 5.2mA 5.2mA 500mV~1.8V 74HC Series 7ns@6V,50pF NAND Gate SOIC-14 Logic Gates ROHSNexperiaLogic Gates
README
README.mdAn 8-bit Computer
My take on breadboard computer designs from Ben Eater (YouTube) and James Bates (YouTube).
Licensing
- The AVR Code for the 7-segment display driver, ALU & Clock are available to use under a MIT license
- The Microcode generator & associated tools are available to use under a MIT license
- All KiCAD design files are licensed Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
- The AVR In-System Programmer AVR includes Peter Fluery's i2c library and is licensed under the GPLv3
- The Included AVR Makefiles are Public Domain.
Parts
323| Qty | Value | Footprint | References |
|---|---|---|---|
| 101 | LED | LED_SMD:LED_0805_2012Metric | D1, D2, D10, D11, D12, D13, D14, D15, D16, D17, D18, D19, D100, D101, D102, D103 +85 |
| 56 | 100n | Capacitor_SMD:C_0805_2012Metric | C1, C2, C10, C11, C15, C16, C17, C18, C19, C20, C21, C22, C23, C24, C25, C26 +40 |
| 27 | 1k | Resistor_SMD:R_0805_2012Metric | R2, R3, R11, R15, R16, R17, R18, R19, R21, R22, R23, R24, R25, R26, R27, R28 +11 |
| 20 | 1k | Resistor_SMD:R_Array_Concave_4x0603 | RN1, RN2, RN3, RN13, RN14, RN15, RN16, RN21, RN22, RN23, RN24, RN25, RN26, RN27, RN28, RN29 +4 |
| 14 | 10k | Resistor_SMD:R_0805_2012Metric | R1, R9, R12, R13, R20, R29, R31, R34, R35, R37, R38, R40, R45, R46 |
| 10 | 10k | Resistor_SMD:R_Array_Concave_4x0603 | RN5, RN6, RN7, RN8, RN9, RN10, RN11, RN12, RN17, RN33 |
| 8 | 74HC245 | Package_SO:SOIC-20W_7.5x12.8mm_P1.27mm | U9, U10, U11, U32, U33, U37, U41, U47 |
| 6 | 74HC1G00 | Package_SO:TSOP-5_1.65x3.05mm_P0.95mm | U35, U36, U39, U40, U45, U46 |
| 6 | 74HC245 | jcf:SOIC-20W_7.5x12.8mm_P1.27mm_Rounded | U2, U15, U17, U21, U24, U26 |
| 6 | 74HC377 | jcf:SOIC-20W_7.5x12.8mm_P1.27mm_Rounded | U6, U14, U16, U22, U23, U25 |
| 4 | 74HC1G32 | Package_SO:TSOP-5_1.65x3.05mm_P0.95mm | U5, U28, U29, U50 |
| 4 | AVRISP | Connector_PinHeader_2.54mm:PinHeader_2x03_P2.54mm_Vertical | J1, J2, J4, J6 |
| 3 | 1u | Capacitor_SMD:C_0805_2012Metric | C12, C13, C59 |
| 3 | 28C64B | Package_SO:SOIC-28W_7.5x17.9mm_P1.27mm | U34, U38, U44 |
| 3 | 74HC161 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U1, U3, U30 |
| 3 | GREEN | LED_SMD:LED_0805_2012Metric | D32, D104, D105 |
| 3 | RED | LED_SMD:LED_0805_2012Metric | D33, D106, D107 |
| 3 | SW_Push | jcf:SW_TH_Tactile_Omron_B3F-10xx_Fixed | SW1, SW4, SW5 |
| 2 | 220k | Resistor_SMD:R_0805_2012Metric | R14, R43 |
| 2 | 3k3 | Resistor_SMD:R_0805_2012Metric | R32, R33 |
| 2 | 47n | Capacitor_SMD:C_0805_2012Metric | C14, C58 |
| 2 | 680R | Resistor_SMD:R_Array_Concave_4x0603 | RN18, RN19 |
| 2 | 74HC157 | jcf:SOIC-16_3.9x9.9mm_P1.27mm_JCF | U7, U8 |
| 2 | 74HC1G08 | Package_SO:TSOP-5_1.65x3.05mm_P0.95mm | U51, U52 |
| 2 | ATmega16-16AU | Package_QFP:TQFP-44_10x10mm_P0.8mm | U20, U43 |
| 2 | SW_DIP_x08 | Button_Switch_THT:SW_DIP_SPSTx08_Slide_9.78x22.5mm_W7.62mm_P2.54mm | SW2, SW3 |
| 1 | 100u | Capacitor_SMD:C_Elec_6.3x7.7 | C55 |
| 1 | 10u | Capacitor_SMD:C_1206_3216Metric | C56 |
| 1 | 22u | Capacitor_SMD:C_1206_3216Metric | C57 |
| 1 | 390 | Resistor_SMD:R_0805_2012Metric | R6 |
| 1 | 4k7 | Resistor_SMD:R_Array_Concave_4x0603 | RN20 |
| 1 | 4k7 | Resistor_SMD:R_0805_2012Metric | R10 |
| 1 | 50k | jcf:BOURNS-3310Y | RV1 |
| 1 | 6264SL | jcf:SOIC-28W-LY6264 | U4 |
| 1 | 7-20V | jcf:PJ-202A | J5 |
| 1 | 74HC00 | jcf:SOIC-14_3.9x8.7mm_P1.27mm_JCF | U12 |
| 1 | 74HC08 | jcf:SOIC-14_3.9x8.7mm_P1.27mm_JCF | U27 |
| 1 | 74HC132 | jcf:SOIC-14_3.9x8.7mm_P1.27mm_JCF | U13 |
| 1 | 74HC14 | jcf:SOIC-14_3.9x8.7mm_P1.27mm_JCF | U49 |
| 1 | 74HC377 | Package_SO:SOIC-20W_7.5x12.8mm_P1.27mm | U31 |
| 1 | ATmega48-20AU | Package_QFP:TQFP-32_7x7mm_P0.8mm | U18 |
| 1 | ATtiny45-20SU | Package_SO:SOIC-8_5.275x5.275mm_P1.27mm | U53 |
| 1 | CAT24C256 | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U42 |
| 1 | CLK | jcf:SW_TH_Tactile_Omron_B3F-10xx_Fixed | SW8 |
| 1 | FJ4401AG | jcf:FJ4401AG | U19 |
| 1 | G*** | jcf:Polarity_marking_center_positive_1.5mm_FrontS | svg2mod |
| 1 | I2C | Connector_PinHeader_2.54mm:PinHeader_1x04_P2.54mm_Vertical | J3 |
| 1 | K7805M-1000R3 | jcf:K78xxM-1000R3 | U48 |
| 1 | MODE | jcf:SW_TH_Tactile_Omron_B3F-10xx_Fixed | SW7 |
| 1 | SW_DIP_x02 | Button_Switch_THT:SW_DIP_SPSTx02_Slide_9.78x7.26mm_W7.62mm_P2.54mm | SW6 |
The 320 most common of 323 parts.
Questions
How big is the 8-Bit CPU PCB?
It measures 158.8 × 104.1 mm and has 4 copper layers, 1.6 mm thick.
What parts does the 8-Bit CPU use?
323 parts, built around the ATMEGA16-16AU, ATMEGA48-20AU, ATTINY45-20SU and 74HC245D. 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 8-Bit CPU KiCad files?
From the frenchie/8-Bit-Computer repository on GitHub, at the commit this page was made from: the board is KiCAD/8-Bit CPU/8-Bit CPU.kicad_pcb. PCBKit opens the board in the browser, with nothing to install.
Can I use the 8-Bit CPU design in my own project?
Its repository states no licence, so its author keeps all rights: ask frenchie before reusing the design.
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