Weird cardridge with infrared - help rev en

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Weird cardridge with infrared - help rev en
by krzysiobal on 2017-11-03 (#207290)
Image Image Image

PRG-ROM and mapper are integrated in blob, so no idea if PRG banks can be switched or not.
Does not work properly in emu as NROM (dumped $8000-$ffff).
It writes something to $4801 and then $4802, but during write cycle, neither 74161.CLK goes down, nor U5A.1

https://www.youtube.com/watch?v=ChP5okfMzD4
Re: Weird cardridge with infrared - help rev en
by cpow on 2017-11-03 (#207291)
Could it be mapper 178?
Re: Weird cardridge with infrared - help rev en
by Fisher on 2017-11-03 (#207293)
Could this be a cartridge of an clone with motion controls?
If I remember correctly there were a few of them when Wii was on top.
I never saw one personally... :-(
Re: Weird cardridge with infrared - help rev en
by krzysiobal on 2017-11-03 (#207295)
No idea, all I have is this cart, but probably yes, because joypad cannot be used to control players during match.

Writing $c to $4801 and then $1 to $4802 as game does, does not change current bank. Maybe there is some additional trick to `unlock` those bank change.

---
edit: Ok, it does change bank, M2 need to be cycling constantly.
Re: Weird cardridge with infrared - help rev en
by cpow on 2017-11-03 (#207296)
krzysiobal wrote:
No idea, all I have is this cart, but probably yes, because joypad cannot be used to control players during match.

Writing $c to $4801 and then $1 to $4802 as game does, does not change current bank. Maybe there is some additional trick to `unlock` those bank change.


The mapper doc says the bank change is committed only when $4801 is written so write $4802 first. The game could just be assuming whatever is behind $4802 has a valid reset default.
Re: Weird cardridge with infrared - help rev en
by krzysiobal on 2017-11-03 (#207297)
1. I think writing order does not match
2. Only D2,D1 from $4801 is taken into account
3. I got working full dump - thank you :))
Re: Weird cardridge with infrared - help rev en
by lidnariq on 2017-11-03 (#207298)
Have you figured out what it's doing with the IR receiver?
Re: Weird cardridge with infrared - help rev en
by krzysiobal on 2017-11-03 (#207301)
IR receiver is probably to control player movemeng in game.
Here it is low level protocol from hardware. How those read bits make commands need to be analyzed from ROM.
But when I light TV remote control into this sensor, the ball is fired so it works :P

Code:
[I... ....] $6000-$7fff (write)
 |
 +---------- 0: pull IRQ to VCC, 1: drive IRQ with data data from IR sensor
 
 
light received --+ +-+ +-+ +-----------
by IR sensor     | | | | | |
                 +-+ +-+ +-+
                  ^_______ some unknown frequency
            
output of      --+         +-----------
IR sensor        |         |
                 +---------+
            
Huge cap at IR sensor causes short pulses to be ignored
--------------------------------------------------------------
[.... ...V] $5000-$5fff (read)
         |
       +-- read current bit from IR sensor (no matter if IRQ is enabled or not)


Hahaha, better than D-pad:
https://www.youtube.com/watch?v=qFrkYxW1ehM
Re: Weird cardridge with infrared - help rev en
by lidnariq on 2017-11-03 (#207305)
Quote:
some unknown frequency
Very likely 38kHz, but I guess 56kHz receivers are not too rare.

Typical bandwidth after demodulation is about 1kHz.

Quote:
Hahaha, better than D-pad:
That's surprisingly compelling.