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you can figure it out using a multimeter:
the 27c010/27c1001 (JEDEC)
CE = Pin 24
A16 = Pin 2

the 27c301/27c1000 (non-JEDEC)
CE = Pin 2
A16 = Pin 24

basically A16 should be shared between all of the ROMs in the same group, while CE will either be tied to ground or shared with only 1 other ROM.

In my experience on the System 16 ROM boards it either uses ALL 27c010 or ALL 27c301, I've not noticed any that are mixed.
Pin 24 is /OE, /CE is pin 22 :)
 
OOOh I am such a n00bcake... I found some pictures of my board that I convertet waaay back.. and I realised that I made the exact same misstake now, as then... 68k cpu pinout starts the adresses at 1!!
How could I forget?! :thumbdown: . After shifting the 4 adresslines +1 all works. (Except the sound, but that I knew from the start).

1 of the datalines is stuck at 2v and /WR, /OE stuck high. Will check that tonight.. too bad all ym2151 I have are fakes :(. lets hope its the sram, ff or just the z80..


Solution:
It was a damaged track on the MB (componentside). There is one looooong track going very close to the pcb edge that was damaged probably from a srewdriver at some point in time when fastening/changing pcb.. that should connect pin14 (D6 on soundbus) of E20 74LS273 to pin63 on the big custom 315-5195, closest to the 68k CPU.

20200604_201420.jpg
 
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Hi guys, i finally have my first 16B, it's a wrestle war but i'd like to play Bay Route on it. Motherboard is a 171-5357 with the 68000+ID875 and rom board is 171-5704.
Did i understood good about eeprom placing? The A row is non-jedec and B viceversa? I will burn the main code on A row to 4x nec 27c1000 128kb, using the decripted files (2 of them).
The rom set is World.
Is that correct?
 
Hi guys, i finally have my first 16B, it's a wrestle war but i'd like to play Bay Route on it. Motherboard is a 171-5357 with the 68000+ID875 and rom board is 171-5704.
Did i understood good about eeprom placing? The A row is non-jedec and B viceversa? I will burn the main code on A row to 4x nec 27c1000 128kb, using the decripted files (2 of them).
The rom set is World.
Is that correct?
Nevermind, it was just like that, exept B row must also be 20c301/1000 non jedec, at least for this game.
I didn't have many of these so i've swapped OE and A16 to a few of regular 20c010. Always wanted to play the Sega's Contra :)
 
Hi. Does anyone have SDI set 2 or SDI set 3 decrypted roms to covert?

Where can I get these roms. :)
 
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