First, be aware that it works only with first batch PSX (like, SCPH1000/1001/1002).
Even if you have an SCPH1002, there's a possibility that it's an already patched console. (Sony patched that issue without changing the console version number). I don't know about USA SCPH1001 models, maybe Sony did the same fix without changing the version number.
There are 2 types of swaps :
Type 1 : Easy 1
- Switch on the Console
- Go to CD Audio player
- Insert an Original PS1 game disc (the more the number of track the better it is. TOC is important here).
- block the sensor with something (I personally use scotch tape I push into the sensor, it works great and better than a pen cap because when it's done, you can close the lid)
- When the game disc stop spinning, swap the disc, close the lid, and exit the CD Audio Player. The game will boot.
Type 1 : Easy 2
- Block the lid sensor with a tape.
- Put an original game disc
- Power on the console
- When the spinning disc goes slower (at the PS Logo), swap the disc.
Pro:
- Really easy methods, no timing needed at all with easy1 method.
Cons:
- You need a big TOC (Table Of Content) game, or games bigger than the original one won't work fully.
ex: if you use a demo disc to play Tomb Raider, you won't have any music in game as it uses CDA tracks which weren't mapped on the demo disc.
- Can't swap the disc in game if you need to change disc number or relaunch the game if it stops reading. (Note by Cyan : Need to be confirmed, I don't remember because I don't use that method at all) (I think it's because it reads the original DiscID and wait for discID of the played game, not the demo one).
Type 2 : harder
- Put an original game disc (any disc, any TOC size).
- Block the lid sensor with the scotch tape.
- Touch gently the optic block with your fingers around the game disc, ready to remove it.
- Pay attention to the sound the optic block will do.
- Power on the console : You will hear the optic bloc starting moving, then doing "tic tic tic", then on your TV you will heard the bios boot sound and see first logo appearing on screen.
While the optic bloc is doing the Tictictic, you can feel with your finger still on the bloc that it's gently taping, it's another way to determine the timing. (it's less than 1 second after powering the console).
You have to swap the disc between the first moving bloc and the "tictictic" sound/sensing.
The "tictictic" thing correspond to the TOC reading, so it will read the TOC from the swapped disc and not the original one.
PS : Sometime the disc may stop before the game launch. Just wait few second or go to the CD Audio player and exit, it will boot automatically.
Pros:
- Reads ANY games, whatever the TOC size.
- Can swap multi disc game with no save prompt (Parasite eve, Chrono Cross, Valkyrie Profile, etc.) when asked to insert disc 2
- Can relaunch the disc when the console stop spinning it in game : Remove the tape, put an original back, put the tape back and swap the disc again before the tictictic feeling/sound. If the disc stops or the game doesn't resume, do it again.
Con:
- None. You just need a little practice. It's not really hard.