# How to stabilise SPI connection

To salvage a server with a broken BIOS, I am attempting to in-situ program a chip via SPI using a Raspberry Pi 3B:

After connecting my clip and wiring it up (and measuring all the leads to ensure I have the correct pinout), I have the problem that all dumped files are different, as well as flashrom not always recognising the chip correctly. This happens at higher and lower clocks (I have tried 32-64-128-256-512 kHz, 10, 9, 8, 7 mHz).

The Flashrom Wiki has a page for common problems and solutions, where they mention using parallel capacitors or series resistors. While googling I found pages of electronics courses which explained you may sum the capacitances of parallel capacitors, but not how to connect them. I suspect there might be other ways to improve the connection as well.

How could I add or remove components in order to get consistent reads with this?

• You may want to include a question in your post. – Blair Fonville Jul 28 '18 at 7:27
• Have you isolated the I/O pins from the original motherboard? Also what is powering it? – Oldfart Jul 28 '18 at 8:47
• @Oldfart the Pi is powering it currently. It can supply around 50mA. I haven't isolated the I/O pins because I think that requires desoldering the chip and I'm a beginner without the necessary tools. I have ordered a simple soldering station though. – Zsub Jul 28 '18 at 9:22