How to use Claude to build an EEPROM upload tool

Will Warren used Claude Code to design and implement the serial protocol for an EEPROM programmer in his homebrew CPU project. The immediate problem was getting generated microcode from a computer onto three physical ROM chips without making every revision a manual programming exercise.

The programmer used an Arduino Nano and shift registers to address and control the EEPROMs. Warren handled the circuit design, wiring and control-signal arrangement. Because the chip's output-enable, write-enable and chip-enable signals passed through the shift-register chain, sequencing those signals correctly mattered before faster writes could be attempted.

Claude's contribution connected the existing microcode workflow to the programmer over serial. The resulting toolchain generated binary ROM data in Python and uploaded it to the hardware. Warren reports that a slow programming mode worked on the first attempt, then describes improving the transfer with page writes instead of individual byte writes.

The larger article follows the CPU into working hardware, but does not attribute every schematic, soldering fix or timing correction to Claude. This is a specific interface-development use case: agent-written protocol code became part of a human-built programming tool, with actual uploads and physical CPU behavior providing the checks beyond compilation.

Prompt
Suggested prompt (written by Agents In Use, not the author's)

Source: Personal blog · Will Warren