Question about 32-in-1

[CrazyImpmon]

Has anyone figured out how to hack the 32-in-1 cart to have switch for selecting games? I don't want to keep flipping the power switch just to look for one game.

 

I' thinking there's a random address generator somewhere that selects one of the 32 games. All 2K games IIRC so it'd be a 64K ROM with some upper address line randomized at power up.

 

If someone could figure the line random and a way to disable them in favor of DIP switches (5 switches should be enough)

[XTClaus]

Oh yes, that would be great...

[CrazyImpmon]

Top side

Bottom

(images are about 320K each, 1280x960) (Sorry I couldn't use my scanner, anything more than 2mm off the glass would come out blurry)

 

The label on my 32-in-1 was so thick the whole thing came off easily so I can restore mine as if it was never opened.

 

It does look like a DIP switch selector can be done. I may not even need to tear apart my game to trace all the lines and make schematic. One of the chip is a CMOS 4024 (7 stage ripple counter)

 

4024, 744024

7-bit asynchronous binary counter with reset.



    +----------+

/CLK |1  +--+ 14| VCC

.RST |2       13|

 Q6 |3       12| Q0

 Q5 |4  4024 11| Q1

 Q4 |5       10|

 Q3 |6        9| Q2

.GND |7        8|

    +----------+



[This information is part of the GIICM]

 

I've misplaced my multimeter once again so I can't really verify this but this is my best guess tracing:

 

Q0 goes to pin 2 of the ROM

Q1 to pin 21

Q2 to pin 26

Q3 goes under the chip and may be going to pin 27 or 28

Q4 goes under the chip and probably goes to pin 1

 

I will try to remove the chip and install a DIP switch from +5v to the pin with a 47K pulldown resistor to ground and see if that lets me manually selects one of 32 games. (47K is used with EPROM multicart but should work with ROM version)

 

The other chip is a 7414 hex inverter/schmitt trigger.

 

I don't have the 128 in 1 but if it's the same as 32 in 1, the same could be used with additional 2 switches and 2 resistors to replace the Q5 and Q6 of the ripple chip.

 

Soldering iron- check

desoldering braid- check

8 pos dip switch- check

small proto board- check

solder- check

wires- check

5x47K resistor- check

sanity- no go.