Talk:TribalTap
From SnesWiki
Contents |
[edit] Compatibility
"snes-d0 here should be pulled high (will read as 0). This will screw up multitap detection in any game that follows Nintendo's recommended programming procedures"
- Are you sure there's a problem with that? Nintendo has released "MultiPlayer5" schematic & source code (found in book2.pdf). The schematic doesn't do anything special with 4017.bit0. And the source code only checks 4016.bit1 (for rejecting multtap on connector 1) and 4017.bit1 (for detecting it on desired connector), but it doesn't check 4017.bit0.
- Did Nintendo release any other docs/drivers that do check that bit? Or are there any games that do so? nocash --77.6.180.221 23:26, 2 June 2011 (UTC)
[edit] Internal State
"It was found to be a Texas Instruments 16L8 PAL. This means the logic is completely combinatorial and thus cannot have an internal state"
- But couldn't it use the logic gates to create a flipflop? For example, with two NOR gates:
SET ___ _____
| NOR \__
__|_____/ |____ /OUT
|____ _____|
\/
____/\_____
|__ _____ |____ OUT
| NOR \__|
CLR ___|_____/
- Like setting the flipflop upon "strobe" signal (aka "latch" signal), and clearing it via "io" signal. At that point, I would change "io" direction from input to output, and send the data for player 6 through that line. Though, according to your info, "io" is wired to an input-only pin on the PAL chip, and so the direction couldn't be changed. nocash --77.6.180.221 23:26, 2 June 2011 (UTC)
[edit] Pin-Outs
"notice nothing depends on B0 (the p6 data line)"
- Hmmmmm, player 6 input is wired to "B0" (PAL Pin 12)? According to datasheets from Texas Instruments and Fairchild, Pin 12 and 19 are outputs (only pin 13-18 are i/o). That'd really explain why it doesn't work :-) nocash --77.6.180.221 23:26, 2 June 2011 (UTC)
[edit] TribalTap6 Schematic
Just tried to combine your descriptions into a schematic. If I didn't got it wrong, it should look as below? nocash --77.6.180.221 23:26, 2 June 2011 (UTC)
_____ _____
| \_/ |
VCC--[RP]-------CLK---> 1|IN0 VCC|20 <---VCC
VCC--[RP]--------IO---> 2|IN1 16L8 OUT7|19 --->IN0 (out-only)
VCC--[RP]-----IN0'A---> 3|IN2 PAL I/O6|18 --->IN1
VCC--[RP]-----IN1'A---> 4|IN3 I/O5|17 --->STB'A
VCC--[RP]---/MODE6P---> 5|IN4 I/O4|16 --->IO'A
VCC--[RP]-----IN0'B---> 6|IN5 I/O3|15 --->CLK'B
VCC--[RP]---/MODE2P---> 7|IN6 I/O2|14 --->CLK'CDE
VCC--[RP]-----IN0'D---> 8|IN7 I/O1|13 --->STB'BCDE
VCC--[RP]-----IN0'C---> 9|IN8 OUT0|12 <---IN0'E (out-only???)
GND -->10|GND IN9|11 <---/STB----[R]---VCC
|_____________|
__________ _______ _______
|3-position| | S9013 | | S9013 | +-[R]-STB
|switch 2P|--/MODE2P | E|-->VCC'BCDE | E|---GND |
GND--| 5P|--NC | NPN B|<--/MODE2P | NPN B|<-------+
| 6P|--/MODE6P | C|---SNES.VCC | C|-->/STB |
|__________| |_______| |_______| +-[R]-GND
______________________________________________________
| (Female)(.............Male........................)| ???--|LED>--???
|Pin SNES PORT2 PORT3 PORT4 PORT5 PORT6 |
|1 VCC VCC VCC'BCDE VCC'BCDE VCC'BCDE VCC'BCDE| further resistors
|2 CLK CLK CLK'B CLK'CDE CLK'CDE CLK'CDE | ???
|3 STB STB'A STB'BCDE STB'BCDE STB'BCDE STB'BCDE|
|4 IN0 IN0'A IN0'B IN0'C IN0'D IN0'E | (not installed)
|5 IN1 (IN1'A) - - - - | diodes ???
|6 IO (IO'A) - - - - |
|7 GND GND GND GND GND GND |
|______________________________________________________|
Note: The PCB has wires to all 7 pins of PORT2,
but the installed connector has only 5 pins, so,
in practice, IN1'A and IO'A are not connected.
