.brgzx (BridgeZX)

BridgeZX moves files from a Windows PC to a ZX Spectrum's SD card over Wi-Fi. .brgzx is the Spectrum-side half: an esxDOS dot command that opens a TCP listener and accepts files pushed by a PowerShell client running on the PC.

The project was originally published under the name bridgezx/wifi.asm using an AY-8912 bit-banged UART; a 2026 rewrite replaced that with a proper divMMC/ZX-Uno UART driver and renamed the shipped command to brgzx.

Usage

.brgzx

No arguments. The command starts the server and waits for a connection; run the Windows client (BridgeZX_FINAL.ps1) to queue and send files.

Requirements

• ZX Spectrum 48K/128K/+2/+3 or compatible clone.
• divMMC/DivIDE-compatible storage running esxDOS.
• ESP8266/ESP-12 Wi-Fi module wired to the UART path used by the divMMC/ZX-Uno driver (not the AY chip - that path was removed in the 2026 rewrite).
• TCP port 6144, reachable from the PC on the same Wi-Fi network.

Notes / behaviour

• Each transferred file carries a CRC-16/CCITT check; the client only advances the queue after a genuine server ACK.
• Files are written directly through esxDOS with free-space checks and a 2 MB per-file limit.
• Timeouts, CRC failures, protected directories, or disk errors stop the queue rather than silently reporting success.

Provenance

Built from server/brgzx (sjasmplus, make dot target: dot.asm + boot.asm + modules/{display,ui,net,crc,util,esxdos}.asm + drivers/divmmc.asm), committed prebuilt in the GitHub repo at tag v0.5.3 ("Release BridgeZX 0.5.3", commit 1182e4d, 2026-06-25).

Credits

M. Ignacio Monge Garcia. https://github.com/IgnacioMonge/BridgeZX (MIT license).