SOIC-8 test clip

Clamps onto a 25-series flash chip in-circuit, no desoldering. The other half of the dump.

CORE KIT 4–8€ Flash & chips

What it does

A SOIC-8 clip is a spring-loaded test clip that grips the eight legs of a SOIC-8 chip so you can read an SPI flash in-circuit, without desoldering it. Firmware usually lives in exactly this kind of chip, and the clip is the fastest non-destructive route to it.

Use cases

Dump without desoldering

Clip onto the flash chip's legs in place and read the whole image, leaving the board otherwise untouched.

Verify a read twice

Take two reads and compare hashes; a mismatch means poor contact, not necessarily a bad chip.

Write a patched image back

The same clip drives writes as well as reads, so you can flash a modified dump back onto the board.

How you use it

Find pin 1 (a dot or bevelled edge on the chip), align the clip's pin-1 lead (usually red) to it, clip on firmly, then read twice and compare:

flashrom -p ch341a_spi -r r1.bin
flashrom -p ch341a_spi -r r2.bin
md5sum r1.bin r2.bin      # the two reads must match

SOIC-8 pinout

Same six-wire SOIC-8 layout as the programmer it clips into. Pin 1 (dot) takes the clip's marked lead.

Variants & pitfalls

Seat all eight legs. A clip that grips only six or seven legs reads garbage or nothing. Reseat it and check by eye before trusting a dump.

Power contention. If hashes differ between reads, the board's own CPU may be fighting for the bus. Power the board down, or lift the flash's power pin, to isolate it.