exxos's Atari, Amiga & retro forum

I'd recently acquired a PS4 as a repair project, and only got around to looking at it over the weekend. Here it is:


It's a little grubby, but all in one piece. Unfortunately it has a long pulsing BLOD.

I'd been made aware that it can be configured to include a UART mode in the bios that will dump fault codes to a serial console, so I thought I'd give it a go.

First thing I had to do was find and remove the NOR package, which is essentially the BIOS. I located it next to a large A on the mainboard (A 16 pin TSOP IC), and removed it:


Then I soldered it to my breakout board for reading in my TL866 Pro:


I dumped 3 copies of the NOR before I erased it and then it was a case of using the PS4 wee tools to patch one of the BIN files to enable the UART. I then flashed the patched file back to the NOR and removed from the adapter, and refitted to the board.

I was then able to attach a lead to some pads on the mainboard, ready for connection to my USB serial adaptor as follows:


Although there are 5 connections, and I soldered them all in, only the UART connections are really required for this to work. And we're ready to go:


So once connected, I connected the terminal software to the USB serial adaptor and powered on the PS4 to see this:


Which is good news because I was worried the APU might need reflowing/reballing, which I simply don't have the kit for, but I may just be able to deal with the RAM ICs, which is what this error message suggests it is.


All this info and more can be found at: PS4 UART Instructions.

New fun! :-)

stephen_usher wrote: 24 Jul 2023 15:15 New fun! :-)

Always :)

I just need to work out which RAM is bad, as although it's block 0/1, quite obvious from this pic:


There are RAM ICs on both sides of the board, and I've yet to discover an image showing both sides...

I suspect the layout may be the same on both sides though.

I can also see if I can determine is any of the ICs are getting particularly hot, which may push me in the right direction.

Interesting stuff. PS4 is getting quite a bit of homebrew these days. The soft-mod works up-to FW v9.0 (so don't go online and update your FW)

alexh wrote: 24 Jul 2023 17:16 Interesting stuff. PS4 is getting quite a bit of homebrew these days. The soft-mod works up-to FW v9.0 (so don't go online and update your FW)

Before I can go online I need to fix it :)

If I can get it going though, I'll certainly look into the soft-mod and I'll be turning off auto updates!!!

If you get it working you might want to look at getting an ESP32-S2 for self-hosting soft-mod. Although to begin with you can use an Android phone.

alexh wrote: 24 Jul 2023 17:41 If you get it working you might want to look at getting an ESP32-S2 for self-hosting soft-mod. Although to begin with you can use an Android phone.

Sounds interesting 😁

I must now look at my ps4 and see whats wrong with it
I did get two mega ste working with a can of contact cleaner and a tooth brush. And put fpu in both. Funny think both were fitting with the HD floppy parts but just one had the epson 340 drive in it


Tom

Tomswork wrote: 24 Jul 2023 23:44 I must now look at my ps4 and see whats wrong with it
I did get two mega ste working with a can of contact cleaner and a tooth brush. And put fpu in both. Funny think both were fitting with the HD floppy parts but just one had the epson 340 drive in it


Tom

Good work with the MSTEs, I guess Atari did their usual mess around with the floppies and fitted a mix of parts based on what was in stock.

What's wrong with your PS4?

It destroyes the os while running and crashs reinstall fixes it for a while. Bad drive bad ram it's a hunt

Tom