As part of an introduction in digital electronics workshop at VCF SW 2024, I prepared this board. The intent was to reduce lookup time for datasheets and being able to just connect the inputs and outputs of various gates and logic ICs without caring too much about power supplies. In addition, this board features DIP-switches, a toggle and slide switch, hexadecimal switches, LED arrays which do have a built in resistor for current limiting, pull-up and -down resistors, and much more.
In addition to all of that, it includes a section for a Z80 CPU, static memory, and a ROM to be able to learn to program and work with 8-bit CPUs.
In the "Latest" folder, you'll find the most up-to-date design files, including:
- Gerber files suitable for popular online PCB manufacturers like PCBWay and JLCPCB. Most manufacturers should be fine with either.
- A Bill of Materials (BOM) in both CSV and PDF formats.
- The full schematics of the board.
The board has been implemented using KiCAD 8. The KiCAD project files are included in this repository.
All inputs of various ICs and gates are on the left side of the indicated gate or IC, while outputs are on the right side of the silkscreen indications. Bi-directional pins are horizontal or on the output side (such as at the Z80 CPU for the data bus).
Many components are already connected to +5V or GND and are indicated by an "arrow up" and "triangle down" respectively. Keep in mind that an LED connected to an IC output with +5V acts as an inverted output due to current sinking.
The top right area also provides a legend of common rules/laws and symbols used in digital electronics (and logic as an extension of it).
Below is a list of materials needed to assemble the PCB.
| Reference | Qty | Description | Footprint | Datasheet |
|---|---|---|---|---|
| C1,C2,C3,C4,C5,C6,C7,C8,C9,C10,C11,C12,C13,C14,C15,C16,C17,C18,C19,C20,C25,C26,C27,C28,C29,C30 | 26 | 0.1uF | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | ~ |
| C21,C24 | 2 | 1uF | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | ~ |
| C22,C23 | 2 | 0.01uF | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | ~ |
| D1,D2 | 2 | D_Schottky | Diode_THT:D_DO-41_SOD81_P7.62mm_Horizontal | ~ |
| DN1,DN2,DN3 | 3 | LED Array | Package_DIP:DIP-20_W7.62mm_Socket | ~ |
| J1,J2,J86,J158,J159,J160 | 6 | Conn_01x10 | Connector_PinSocket_2.54mm:PinSocket_1x10_P2.54mm_Vertical | ~ |
| J3,J16,J17,J18,J19,J20,J21,J22,J23,J24,J25,J26,J27,J28,J29,J30,J31,J54,J55,J56,J57,J58,J59,J60,J61,J62,J63,J64,J65,J66,J67,J68,J69,J89,J99,J100,J102,J109,J110,J111,J112,J113,J114,J122,J123,J125,J126,J133,J137,J138,J142,J144,J145,J146,J147,J148,J149,J150,J151,J152,J153,J154,J155,J156,J157,J163,J168 | 67 | Conn_01x02 | Connector_PinSocket_2.54mm:PinSocket_1x02_P2.54mm_Vertical | ~ |
| J4,J5,J6,J7,J8,J9,J10,J11,J12,J13,J14,J15,J32,J33,J34,J35,J36,J37,J38,J39,J40,J41,J42,J43,J44,J45,J46,J47,J48,J49,J50,J51,J52,J53,J70,J71,J72,J73,J74,J75,J76,J77,J78,J79,J80,J81,J87,J106,J107,J108,J135,J136,J141,J143,J167,J169 | 56 | Conn_01x03 | Connector_PinSocket_2.54mm:PinSocket_1x03_P2.54mm_Vertical | ~ |
| J82,J83,J84,J85,J98,J103,J121,J124,J161,J162 | 10 | Conn_01x06 | Connector_PinSocket_2.54mm:PinSocket_1x06_P2.54mm_Vertical | ~ |
| J88,J90,J91,J101,J104,J105,J164,J165,J166,J173,J174 | 11 | Conn_01x08 | Connector_PinSocket_2.54mm:PinSocket_1x08_P2.54mm_Vertical | ~ |
| J92,J93,J94,J172 | 4 | Conn_02x02_Odd_Even | Connector_PinHeader_2.54mm:PinHeader_2x02_P2.54mm_Vertical | ~ |
| J95 | 1 | Barrel_Jack_Switch | Connector_BarrelJack:BarrelJack_Horizontal | ~ |
| J96 | 1 | USB_B_Mini | Connector_USB:USB_Mini-B_Tensility_54-00023_Vertical | ~ |
| J97,J115,J117,J127,J128,J129,J130,J131,J132,J139,J140,J170,J171 | 13 | Conn_01x04 | Connector_PinSocket_2.54mm:PinSocket_1x04_P2.54mm_Vertical | ~ |
| J116,J118,J119,J120,J134 | 5 | Conn_01x05 | Connector_PinSocket_2.54mm:PinSocket_1x05_P2.54mm_Vertical | ~ |
| R1,R2,R3 | 3 | 10k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | ~ |
| R4,R5,R6,R7 | 4 | 1k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | ~ |
| RN1,RN2,RN3,RN4,RN5 | 5 | R_Network10 | Resistor_THT:R_Array_SIP11 | http://www.vishay.com/docs/31509/csc.pdf |
| RV1 | 1 | R_Potentiometer | Potentiometer_THT:Potentiometer_Bourns_3386P_Vertical | ~ |
| RV2 | 1 | 1M | Potentiometer_THT:Potentiometer_Bourns_3386P_Vertical | ~ |
| SW1,SW5,SW6,SW7,SW8 | 5 | SW_Push | RetroStackLibrary:SW_SPST_Push | ~ |
| SW2 | 1 | SW_DPDT_x2 | RetroStackLibrary:SW_DPDT_Push | ~ |
| SW3,SW4 | 2 | SW_DIP_x04 | Package_DIP:DIP-8_W7.62mm | ~ |
| SW9 | 1 | SW_SPDT | RetroStackLibrary:SW_SPDT_Toggle | ~ |
| SW10 | 1 | SW_Push_DPDT | RetroStackLibrary:SW_DPDT_Slide_RightAngle | ~ |
| SW11,SW12 | 2 | Hex Switch | RetroStackLibrary:SW_Hexadecimal_Horizontal | https://www.ckswitches.com/media/1333/cd.pdf |
| U1 | 1 | 74LS07 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | www.ti.com/lit/ds/symlink/sn74ls07.pdf |
| U2 | 1 | 74LS04 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS04 |
| U3 | 1 | 74LS266 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | ~ |
| U4,U5 | 2 | 74LS00 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/gpn/sn74ls00 |
| U6 | 1 | 74LS08 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS08 |
| U7 | 1 | 74LS86 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | 74xx/74ls86.pdf |
| U8 | 1 | 74LS32 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS32 |
| U9 | 1 | 74LS02 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/gpn/sn74ls02 |
| U10 | 1 | 74LS244 | Package_SO:SOIC-20W_7.5x12.8mm_P1.27mm | http://www.ti.com/lit/ds/symlink/sn74ls244.pdf |
| U11 | 1 | 74LS245 | Package_SO:SO-20_5.3x12.6mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS245 |
| U12 | 1 | 74LS51 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/ds/symlink/sn74ls51.pdf |
| U13 | 1 | 74LS174 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS174 |
| U14 | 1 | 74LS175 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS175 |
| U15 | 1 | 74LS373 | Package_SO:SO-20_5.3x12.6mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS373 |
| U16 | 1 | 74LS112 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS112 |
| U17 | 1 | 74LS107 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS107 |
| U18 | 1 | 74LS161 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS161 |
| U19 | 1 | 74LS163 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS163 |
| U20,U21 | 2 | 74LS194 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS194 |
| U22 | 1 | 74LS283 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS283 |
| U23 | 1 | 74LS85 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | http://www.ti.com/lit/gpn/sn74LS85 |
| U24 | 1 | NE556 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | http://www.ti.com/lit/ds/symlink/ne556.pdf |
| U25 | 1 | Z80CPU | Package_DIP:DIP-40_W15.24mm_Socket | www.zilog.com/manage_directlink.php?filepath=docs/z80/um0080 |
| U26 | 1 | ROM_27256 | Package_DIP:DIP-28_W15.24mm | ~ |
| U27 | 1 | CY7C199 | Package_DIP:DIP-28_W7.62mm | ~ |
To work with this KiCAD project, you'll need the RetroStack libraries for KiCAD. Please follow this link to access and install these libraries.
RetroStack is passionate about exploring and preserving the legacy of older computer systems. BitStack is a sub-project of RetroStack, focusing on education in digital electronics. My work involves creating detailed documentation and videos to share the knowledge. I am also dedicated to reviving these classic systems by reimplementing them and offering replacement parts at no cost. If you're keen on supporting this unique project, I invite you to visit my Patreon page. Your support would be immensely valuable and greatly appreciated!
This project is licensed under the MIT License - see the LICENSE file for details.
