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

 

You can disassemble the source code from the upgrade images if you want ... the processor is a freescale (ex Motorola) coldfire on the ultra/p2k/command station. I have looked at it. But it is not a small amount of code. I have the assembly around somewhere and I can tell you some things about it ... such as - the operating system loads all of the preset FLASH information into RAM at start up and thereafter does not access the preset region of FLASH again. There are three valid sizes of DRAM that you can have. A few other things I looked into, like the format of the presets. As I recall they were organised kind of like a file system but its been a couple of years and the details are hazy...

Rather than decode the information via the software disassembly I was going to make a programmer/reader board which would have the capability of reading existing ROM (and FLASH) SIMMs so that the information on them could be decoded from the image. There is the preset area and the waveform area. With some help from the disassembly it should be possible to figure out what all the values do and thereby reproduce the ROM format.

This board was also produced but had the same processor as the FLASH SIMM I'm making and so had the same pinout problem. I have already reworked the CAD files for this board and so could remake a working version. The main purpose of the board is to allow me to program the micro, and CPLD and gain access to the debug serial port of the micro. [the idea is that if you plug the FLASH SIMM into a different SIMM socket upside down these ports become accessible]

Now that I think about it, the SIMMs that I have made (see the pictures on P2K forum) could be used without the micro. If I populate the power supply, CPLD, FLASH and buffer then the devices could be programmed on the development board and made available... of course they wouldn't be able to be reprogrammed (without a development board) but it would be a cheap way to get hold of the equivalent of 4 ROMs with any images you want.

One of the things I would like to do is merge the 16M ROMs (eg protozoa) into a single 32M ROM image so that you could infact have the equivalent of 5 SIMMs in  your P2K.

From: Matthew Howell <misterinterrupt@...>
To: xl7@yahoogroups.com
Sent: Thursday, 11 July 2013 10:38 AM
Subject: Re: [xl7] [p2k] Any interest remaining in a self-programming FLASH SIMM?

 

Not to veer off topic, but does the OP or anyone else know much about the OS? I don't know much about the board yet, though I'm interested in checking it out more. The OP mentioned the rom data format and that made me wonder if perhaps progress has already been made on discovery in this area.

On Jul 10, 2013 5:20 PM, "Alwyn" <zardac@...> wrote:

 

I'm still keen/interested.

On 11 July 2013 08:00, Matt <somatt@...> wrote:

 

WHERE IS THE OP

On Jul 10, 2013 4:44 PM, "Jason Budris" <jsunbud@...> wrote:

 

I'm interested! I presume these will work with the command stations?

Thanks in advance!

Jason

On Jul 10, 2013, at 9:29 AM, Nathan Steele <XTCaine303@...> wrote:

 

YES! especially if the price is reasonable. the ability to put your own sounds in is better than any other ROMS.

On 7/10/2013 9:23 AM, Bruno wrote:

 

---------- Forwarded message ----------
From: woodsworth1 <woodsworth1@...>
Date: 2013/7/10
Subject: [p2k] Any interest remaining in a self-programming FLASH SIMM?
To: p2k@yahoogroups.com

 

Hi.

Couple years back I started a project to build a FLASH based SIMM for proteus 2000 systems that acted like mulitple SIMMs at the same time. Basically you could put this one SIMM in one socket with the others empty and it could look like you had SIMMs in all 4 sockets. I got pretty far along the path of making it (even getting some PCBs made) when I discovered that I had the pin outs of the microcontroller (that allowed you to program the FLASH devices via a usb connection) wrong and the at the boards were just scrap. I posted a picture of the boards in the group. I was annoyed at myself so I dropped the bundle.

Well... I was thinking that the idea is still sound (though I wasted a lot of $$) and I could finish it off if there was sufficient interest in the thing.

What good is it? Well you could have any four ROM SIMMs in you system that you choose. You could reprogram it as you want. And in theory (if we can decode the format of the contents - shouldn't be too hard) you could author your own ROM images and download them , then create your own presets and hard code them onto the device as well. It would be a bit of messing about to achieve the results but if people are prepared to put in the effort...

so is anyone interested?