Mod V3 Console - test picture

[Katagia]

Hi

After modding a V14 and V9 console I tried to mod a V3 console
of a friend.
After getting really pissed off (sorry for that word) by soldering 8
wires direct at the bios? the console won't but up anymore.

I only see a test picutres with white, yellow, cyan, green, mangenta
stripes and a testtone at 1kHz.

Anyone got a tip what when wrong modding the console?
It's a marsII chip.

Cheers,

[l_oliveira]

you shorted a pin on the Mechanics Controller (the square chip with 144 pins, which points A,B,C,D,E,F,G,H and I go to) with the GND and that did activate the test mode.

You should clean it carefully and it should be back to a working state. Don't insist with putting discs while it's not working properly to avoid frying the laser diodes or focus coils(in the 400B laser unit).

[Katagia]

You are right, on epin was shorten. I had many diffigulties to led the wires at the mechanics controller.
No pins are shorten anymore but I'm unsure the pins are still connected with the PCB.
Is it enough these wires are only connected to the modchip?

[l_oliveira]

Unfortunately, if you break the copper tracks on the motherboard, it will stop working, regardless of the modchip being installed or not. The lines the modchip tap in is a 8 bit bus used by the mechanics controller to communicate with the DVD/CD DSP (the big chip where you connect the S wite at the pin 1).

[Katagia]

I don't know I break some wires.
Didn't managed it to get to work
I think I will search for a broken ps2 to get
one working.

Is it possible to connect 4 wires to the mechanics controller and
4 wires at the DVD/CD DSP?
This would make it much easier to solder (with my equipment )

Do you know how a modchip talks with both ICs?
Is this a real bus and the modchip is just a member of the bus?
Is the bus realized as "open collector" and the modchip just pulls
the lanes of the bus to ground when unwanted commands are
transmitted?

Cheers,

[l_oliveira]

1- Yes pretty possible and I've seen people doing that for making the install easier.

2- The MechaCon bus is a tri-state LVTTL (3.3v) bus. The mod chip taps the 8 datalines and the chip select which goes from the MechaCon to the DVD DSP. It doesn't need to know in which direction the data is flowing, it just have to know what data need to be patched. The whole copy protection check hardware is inside the CD/DVD DSP chip and the MechaCon does read it.
The mod chip patches the data returning to the MechaCon chip making it think the disc in the drive is a original copy of a PS2 game. So it doesn't send a stop disc command and lock access to the DVD drive (making the red screen show up)

Trying to explain this better, The modchip usually a high speed CPLD device is programmed to search for specific bit streams and latch lines to GND in a propaer way making the mechacon think the game is original. Te same thing is made with the bios bus to disable the Disc-ID check which is made by the I/O processor acessing the DVD/CD DSP registers.

The 1st modchip to ever hook on the mecha bus had the interesting effect of allowing one to play any region originals but no botlegs. Then people figured out it was possible to use a GameShark/Action Replay to bypass the Disc-ID check and play copies. If you want to know about that chip, it's name is OrigaChip

I don't know I break some wires.
Didn't managed it to get to work
I think I will search for a broken ps2 to get
one working.

Is it possible to connect 4 wires to the mechanics controller and
4 wires at the DVD/CD DSP?
This would make it much easier to solder (with my equipment )

Do you know how a modchip talks with both ICs?
Is this a real bus and the modchip is just a member of the bus?
Is the bus realized as "open collector" and the modchip just pulls
the lanes of the bus to ground when unwanted commands are
transmitted?

Cheers,

[Katagia]

Thank you l_oliveira.