Emu XL-7 & MP-7 User's Group

sdram doesn't appear to be very expensive: 
http://www.mouser.com/ProductDetail/ISSI/IS42S32400E-6TL/?qs=sGAEpiMZZMs6Aik9Fp479t%252bl%252bQagjxNmUHTHvf3qmPA%3d

Didn't spend a lot of time checking into it though.  

I understand the USB option, I don't think I would want it plugged into the computer at the same time as the emu was on, I worry about power isolation.  
I still like the SD card option with a a case modification (A nibbler is inexpensive) since it allows standalone operation, and is operating system agnostic.  

The AVR you show on the schematic supports SPI so it should be fairly simple to get an SDCard on board, perhaps support both SDCard via ribbon cable and an external mount, and a USB option?

Andre


On Thursday, July 17, 2014 12:31 AM, "Andre Lewis bassmeister3000@yahoo.com [xl7]" <xl7@yahoogroups.com> wrote:
 


  
Ah just found your flash rom images from 2010: Yahoo! Groups
  
             
Yahoo! Groups
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On Wednesday, July 16, 2014 2:40 PM, "Jack Pratt woodsworth1@... [xl7]" <xl7@yahoogroups.com> wrote:
 


  
On the board I have designed there is a SDRAM part. This is because the micro I selected supports SDRAM and having the SDRAM  could speed up USB transfers and writing to the FLASH memory. It was not for the P2K hardware to access.

At the moment I am really annoyed at atmel because the upgrade of the firmware in my JTAGICE3 'succeeded' but has turned it into a brick which the computer can not recognise. This is stopping me from dumping the contents of a ROM SIMM which will tell what the image looks like.

If I can figure out what people really want in a FLASH SIMM then perhaps I can work further on this project...



________________________________
 From: "janoch23@... [xl7]" <xl7@yahoogroups.com>
To: xl7@yahoogroups.com 
Sent: Thursday, 17 July 2014 7:19 AM
Subject: Re: [xl7] Any interest remaining in a self-programming FLASH SIMM?
 


  
Ok, an old post of yours mention DRAM. Was hoping maybe you had figured out some clever scheme to squeeze in refresh cycles while the P2k was busy doing other things.

Anyway, are you back to working on this? Can we help in any way to make it happen, such as donating money?



---In xl7@yahoogroups.com, <woodsworth1@...> wrote :


It would be too expensive to provide 32MB of SRAM, even VSRAM to simulate a single slot. It is better to have FLASH memory which is reprogrammed by the microcontroller on cue. (either from an SD card under the appropriate circumstances or via USB).