FAQ
TL;DR: 16 × 15 cm PCB [Elektroda, zaxoniec, post #14461337]; “DipTrace crushed Eagle in intuitiveness” [Elektroda, zaxoniec, post #14506791] DIY clone shrinks the Amstrad CPC 464, adds 3 expansion slots, floppy-to-SD support, and runs on ≈ 2 A @ 5 V [Elektroda, zaxoniec, post #14542501]
Why it matters: It shows how to revive 1984-era hardware with off-the-shelf parts and modern fabrication.
Quick Facts
• PCB size: 160 mm × 150 mm (single board) [Elektroda, zaxoniec, post #14461337]
• Power draw: approx. 2 A at 5 V [Elektroda, zaxoniec, post #14542501]
• China fab turnaround: 7–9 days incl. shipping [Elektroda, zaxoniec, post #14506791]
• Rare 40010 gate-array price: ~PLN 120 (≈ USD 30) [Elektroda, zaxoniec, post #14468364]
• On-board RAM: 64 KB 4164 DRAM; up to 512 KB extra via X-Mem card [Elektroda, zaxoniec, post #14482350]
How long did it take to redraw and route the motherboard?
About 3–4 nights, including building a custom parts library in DipTrace [Elektroda, zaxoniec, post #14461445]
Which key differences exist between the clone and a stock CPC 464?
It swaps the 40007 gate array for the CPC 6128’s 40010, adds a PS/2 keyboard interface, optional 6128 ROM, three expansion slots, and a footprint for an HxC floppy-to-SD emulator [Elektroda, zaxoniec, #14461337; #14484455].
Why keep 4164 DRAM instead of modern SRAM?
4164 chips cost pennies and match the CPC refresh scheme; replacing them needs multiplexers and D-in/D-out separation, complicating routing [Elektroda, zaxoniec, post #14461677] An SRAM swap saves space but breaks timing unless extra logic is added [Elektroda, Anonymous, post #14473993]
What was the biggest bring-up failure?
Power was wired backwards to all 4164 DRAMs, killing memory until the trace was fixed—common when assuming 74xx pin-outs [Elektroda, zaxoniec, post #14461337]
How do I order a similar PCB from China?
- Export Gerbers from DipTrace.
- Upload to a low-cost fab, pick 1.6 mm FR-4, 2-layer.
- Pay; expect shipment in ≈ 7 days [Elektroda, zaxoniec, post #14506791]
What display connection is used?
The board outputs RGB with composite sync; author plugs it into a TV/monitor via SCART. VGA is possible only on monitors supporting sync-on-green [Elektroda, zaxoniec, #14468656; ArturAVS, #14469068].
Can I add Ethernet or Wi-Fi?
Yes. The clone’s edge connector exposes the CPC bus, so projects like Spectranet (ZX Spectrum) can be adapted for telnet-based BBS access [Elektroda, zaxoniec, post #14543308]
Is the design or kit available for purchase?
The author plans to release Gerbers and offer limited "KITS"—PCB, case, and hard-to-find ICs—after rev. 2.0 testing [Elektroda, zaxoniec, post #14467983]
What does the grey "tile" with an SD card do?
It’s an HxC floppy emulator that mimics a 3-inch drive using SD images; the CPC sees standard 180 KB-per-side disks, not gigabytes [Elektroda, zaxoniec, post #14515095]
How many PCB layers and what routing method were used?
Two layers; DipTrace’s autorouter handled most traces with minor manual tweaks [Elektroda, piotr411, post #14488311]
Which expensive parts must I source early?
The 40010 gate array (~PLN 120) and HD46505 CRT controller (USD 7–10) are scarce; Z80, 8255, and 4164 DRAM remain common [Elektroda, zaxoniec, post #14468413]
What operating systems run on the clone?
CP/M Plus, BASIC 1.1, and SymbOS—a multitasking GUI shown running from SD on a 4 MHz Z80 [Elektroda, zaxoniec, #14506791; #14541081].
