EEPROMS

[arudzki]

Does anyone have the code or schematic required to read or write from an EEPROM (SPI Mode) contained in a cartridge? Odd question, I know. I'm making a bit of hardware that goes into the left hand cart slot and would like to store and read values to the EEPROM. The stickler is that the EEPROM also contains a unique serial number which is why I am using the part in the first place.

 

Has anyone done this?

 

 

Thanks

 

Tony

[HiassofT]

Does anyone have the code or schematic required to read or write from an EEPROM (SPI Mode) contained in a cartridge? Odd question, I know. I'm making a bit of hardware that goes into the left hand cart slot and would like to store and read values to the EEPROM. The stickler is that the EEPROM also contains a unique serial number which is why I am using the part in the first place.

 

Has anyone done this?

I guess candle might have done something like this before :-)

 

Other than that, have a look at this project: http://sbc.rictor.org/io/SPI.html

 

With some minor modifications it should basically be all you need (and you don't have to worry about bit-banging the SPI protocol in software from your code).

 

so long,

 

Hias

[falcon_]

Does anyone have the code or schematic required to read or write from an EEPROM (SPI Mode) contained in a cartridge? Odd question, I know. I'm making a bit of hardware that goes into the left hand cart slot and would like to store and read values to the EEPROM. The stickler is that the EEPROM also contains a unique serial number which is why I am using the part in the first place.

 

Has anyone done this?

 

Thanks

Tony

 

Hi arudzki. My first thought is why SPI mode? I2C is at least as easy, and already been worked on, through the joy ports.

http://www.atariage.com/forums/topic/135092-i2c-interfacing-with-8-bits I think there is also software bitbang SPI drivers somewhere that can be adapted if you don't mind using the code-space for it.

 

Also, in Post 7 Hiassoft there made some i2c software available. Very kewl.

But that was two years ago. Hiassoft -- Anything newer on the i2c files of yours? Looking at that rictor.org page, that's a big addition, being a whole fpga chip to take care of the interface. I like the software method best if possible. The speed is not needed here.

 

Curious - what is your project? A portable savegame box?

 

peace!

=falcon

[arudzki]

Curious - what is your project? A portable savegame box?

 

peace!

=falcon

 

 

Actually, I was looking at doing an TCP/IP cartridge for the 8-bit. I know others have / are working on one, but everyone seems to be taking the Crystal 8900 approach, when there are better(in my opinion) options out there. I could be wrong, but thats the point in prototyping, right?

 

So, why the need for SPI? Microchip makes an eeprom that contains a 48 bit unique address that they suggest can be used as a MAC address if additional bits (0xFFFF) are inserted in the middle. I was thinking that it might be good to have on board storage for internet addresses/ports as well as being able to read that 48/64 bit number.

 

Tony

[HiassofT]

Hiassoft -- Anything newer on the i2c files of yours?

Ah, no. I haven't done anything with I2C since then. The code works fine so I also didn't feel the need to change it :-)

 

Looking at that rictor.org page, that's a big addition, being a whole fpga chip to take care of the interface. I like the software method best if possible. The speed is not needed here.

OK, if speed doesn't matter you can do bitbanging. I was thinking more of larger EEPROMs (or even SD cards interfacing to SPI) where bitbanging in software would be far too slow.

 

so long,

 

Hias