CPLD for instead 27C256

[xdev]

27c256 projects

Dear Sir,
I want to instead 27C256 with CPLD. What number for use ?
...Khobkhun

 

[eltonjohn]

Re: CPLD for emulate 27C256

EMULATE ?? is definitly a wrong word here ! But i kind undesrtand you
YOU WANT to map adresses to SOME DATA WRIGHT ??

well a 27C256 has 15 inputs + CE + CS = 17 inputs
now you need a 8 output cells for the data ,so i suggest something like the XC7272 or the XC7236 IN GENERAL LOOK FOR A ANY EPLD WITH AT LEAST 25 I/Os
This is in the case you want to map all 15 INPUTS but if you need only 12 or less you coud use a 22v10
Now this chips don't come in DIP form .. so you will have to rewire them
o make an adaptor .. and pf course to program them ..
But the fact that you don't even know how to chose an EPLD .Leads me to beleive that this is not your piece of cake!

 

[xdev]

CPLD for emulate 27C256

My project want to use CPLD instead 27C256 in Gameboy cart.

 

[jelydonut]

Re: CPLD for emulate 27C256

so you want to use a cpld as a rom?

it can be done.. but i don't think your gonna find a cpld big enough to fit a whole rom.. and if you do it probably won't be cheap..

i don't see the advantage of that though..

jelydonut

 

[davorin]

Re: CPLD for emulate 27C256

And beware that Gameboy cartridge is 5V!

 

[xdev]

Gameboy Advance is 3.3V

 

[davorin]

Okay..you got me there (o;

But why don't you use regular flash memory? Much cheaper than a FPGA with 256kBit built-in RAM (no CPLD with RAM yet or 256k registers ;o).

Most probably you need an addition CPLD anyway for decoding/bank switching (guess GBA also uses some MBC stuff). And with JTAG you could program the flash through CPLD in-system as well...

 

[Big Boy]

I think it would be simpler to simply use flash memory... no?

 

[eltonjohn]

Xdev ..
explain yourself better man!... the element that you gave .. i understood that you wanted to map some addressing space to very simple DATA !
let's say you want to address 0000h - 0FFFH to contain some value x
and other adresses to 1000h - 1FFFH to contain some value y

Thats' the only logical thing implied in your REQUEST .. because is evident that a CPLD only has 8 - ~512 Cells for the biggest ones so FROM 1 BYTE to 64 BYTES .which is nothing ..
NOW PROBABLY you want to use a GAMEBOY CATRIDGE to CONTROL something and you need just a DROP IN CPLD to replace an EPROM ON A GAMEBOY ADVANCE .. .THAT MAKES SENSE !!!!!

THEN I WAS RIGHT you don't need to decode all 15 ADDRESSES but just a FEW .. there are some 22v10 that must be 3.3
The GAMEBOY ADVANE IS AN INEXPENSIVE NEAT MACHINE !
Also there are some projects on the NET ..

 

[davorin]

Check here: https://www.devrs.com/gba/hardware.php#harddev

or better: https://www.gbadev.org/hardware.php

 

[xdev]

Dear Sir,
I can write, speak English a little. Sorry for all.

 

[eltonjohn]

Ok i absolve you my son !
IN NOMIS PATRIS ET SPIRITUS SANCTUS!
go in PEACE

cheers

PS .. no BIG DEAL this is a great place .. try your best .. your english will get better and somebody will always try to help you !