FISC
About the FISC PCB
FISC is an open source PCB design by DoctorWkt, published on GitHub under the GPL-3.0 license. It is a 2-layer board measuring 231.3 × 96.5 mm, with 59 components from 26 distinct parts.
Other key parts include the DS1233-10+, 74LS593, 74HCT138, 74HCT240 and 74LS469. By type, the board carries 27 ICs, 26 capacitors, 5 connectors and 1 switch.
From the project
An 8-bit TTL CPU with a Stack Pointer
Please note: The FISC design has some major flaws. Rather than fix them, I've incorporated the fixes into the next version of the design: .
FISC is an 8-bit microseqenced CPU wth a 64K address space built from discrete TTL-level components. It provides:
+ recursive Functions, + Indexed addressing and + Stack operations
as well as the usual load/store and arithmetic operations, comparisons, branches and jumps.
Main components on the FISC
FISC bill of materials (BOM)
59 components, 26 distinct parts.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | DS1233-10+ | TO-92 | IC1 |
| 2 | 74LS593 | DIP-20_W7.62mm_Socket | U1, U2 |
| 2 | 74HCT138 | SOIC-16_3.9x9.9mm_P1.27mm | U3, U19 |
| 1 | 74HCT240 | SOIC-20W_7.5x12.8mm_P1.27mm | U4 |
| 2 | 74LS469 | DIP-24_W7.62mm | U5, U6 |
| 7 | 74HCT574 | SOIC-20W_7.5x12.8mm_P1.27mm | U7, U8, U11, U12, U13, U14, U17 |
| 1 | AS6C1008 | DIP-32_W15.24mm | U9 |
| 1 | AT28C64B | DIP-28_W15.24mm | U10 |
| 2 | 74HCT541 | SOIC-20W_7.5x12.8mm_P1.27mm | U15, U16 |
| 1 | 74HCT161 | SOIC-16_3.9x9.9mm_P1.27mm | U18 |
| 1 | 74HCT151 | SOIC-16_3.9x9.9mm_P1.27mm | U20 |
| 1 | 74HCT139 | SOIC-16_3.9x9.9mm_P1.27mm | U21 |
| 1 | 74HCT154 | SOIC-24W_7.5x15.4mm_P1.27mm | U22 |
| 1 | M27C322-100F1 | DIP-42_W15.24mm | U23 |
| 1 | UM245R | DIP-24_W15.24mm_Socket | U24 |
| 1 | AT27C1024-70PU | DIP-40_W15.24mm | U25 |
| 1 | ECS-100AX-035 | Oscillator_DIP-14 | U26 |
| 1 | Data Bus Pin Header | PinSocket_1x10_P2.54mm_Vertical | J1 |
| 1 | Address Bus Pin Header | PinSocket_1x18_P2.54mm_Vertical | J2 |
| 1 | uSeq Pin Header | PinSocket_1x06_P2.54mm_Vertical | J3 |
Show 6 more
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | Control Lines Pin Header | PinSocket_1x18_P2.54mm_Vertical | J4 |
| 1 | Clock Pin Header | PinSocket_1x02_P2.54mm_Vertical | J5 |
| 1 | SW_Push | Push_E-Switch_KS01Q01 | SW1 |
| 24 | 0.1uF | C_0603_1608Metric_Pad1.05x0.95mm_HandSolder | C1, C2, C3, C4, C5, C6, C7, C8 +16 |
| 1 | 220uF | CP_Radial_D8.0mm_P5.00mm | C25 |
| 1 | 0.01uF | C_0603_1608Metric_Pad1.05x0.95mm_HandSolder | C27 |
FISC design files
The KiCad project lives in the DoctorWkt/FISC repository on GitHub; these links point at the commit this page was built from.
- LayoutKicad/FISC.kicad_pcb
FISC: common questions
How big is the FISC PCB?
The FISC measures 231.3 × 96.5 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the FISC?
59 components, from 26 distinct parts. The full bill of materials is listed on this page.
Where can I download the FISC design files?
From the DoctorWkt/FISC repository on GitHub, which has the KiCad layout; the links under Design files point to each one.
Can I use the FISC design in my own project?
Yes, under the terms of its GPL-3.0 license, which DoctorWkt chose for the repository.