How it works

This interface buffers programming signals between a hardware PC parallel port and a target flash device. The target supports serial programming over JTAG while exposing a parallel interface during normal operation, allowing firmware to be updated without removing the memory.

The original design uses PSDsoft Express and includes a two-sided PCB measuring 75.1 × 60.0 mm. The surviving PCB and document archives are preserved as historical resources; compatibility with a modern computer is not established.

Original archive figures

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Figure 1 · NewCircuits archive · Download image ↓

On the bench

Use the exact target pinout and logic levels. A USB printer adapter is not a drop-in hardware parallel port. The original claim that errors in ST’s schematic were fixed has not been independently verified.

Resources & provenance

Rewritten from the original projects/new/al83nb47_prjnew001.php page. Component values and historical performance claims have not been independently bench-tested.

Browse all surviving downloads →