[Coco] CoCo SDC - using the flash banks

Shane Broadbent shanetb at telstra.com
Sat Mar 1 23:23:38 EST 2014


Darren A <mechacoco at ...> writes:

> 
> On Sat, Mar 1, 2014 at 3:47 PM, Shane Broadbent <shanetb at ...> wrote:
> 
> >
> > Hi Darren, so do you require an actual Program Pak or is there a procedure
> > to do this using a .ccc file. I have a bunch of those but cannot think of
> > how this would be done. I do not have a Multi-Pak, so just wondering if
> > there are other options. Something else I tried was to use your flash
> > updater tool, and simply renamed a 16k .ccc file to sdc-dos.101 and then
> > ran
> > the update...again, no error but it did not work 
> >
> 
> This is an operation that requires a bit of effort. What is needed is to
> get the contents of the CCC file into RAM on the CoCo so that it can be
> written to the Flash.  The first step is to convert the CCC file to a BIN
> file so LOADM can be used to load it. Use a Hex Editor application on your
> PC to insert a 5 byte pre-amble at the beginning of the file and a 5 byte
> post-amble at the end.
> 
> Pre-amble:   00 nnnn 4000
> 
> The first byte (00) indicates this is a pre-amble. The next two bytes
> (nnnn) specifiy the size of the ROM data (original size of the CCC file).
> The last two bytes (4000) are the address in RAM where the data will be
> loaded. The pre-amble for an 8K cartridge would be 00 2000 4000.
> 
> Post-amble:   FF 0000 B44A
> 
> The first byte (FF) indicates this is a post-amble. The next two bytes are
> both zero since no more data will be loaded. The last two bytes (B44A) are
> an address which will produce an ?FC ERROR if you happen to enter EXEC
> after LOADMing the file.
> 
> Once you have a BIN equivalent of the CCC file you can use the "wimgtool"
> utiltiy from the MESS distribution to insert it into a DSK image. With the
> DSK image mounted via SD card or DriveWire you can LOADM the BIN file, but
> first you need to reserve the RAM above $4000 to hold the data:
> 
> CLEAR 200, &H4000
> 
> LOADM "filename
> 
> Finally, write the data to the desired Flash bank:
> 
> WRITE MEM  <at> bank, &H4000,&HC000,&H3E00
> 
> Darren
> 
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> 
> 


Excellent, thanks for the detailed explanation Darren.

With that info, I was able to get games running from flash.

I picked 4 random 8K ROM PAKs,

Canyon Climber
Don Pan
Mega Bug
Star Blaze

and then tried a 16K PAK,

Thexder.

For the 16K PAK used

Pre-amble:  00 4000 4000

Post-amble: FF 0000 B44A

I also went back to one of my original thoughts and after adding the pre &
post amble to the Thexder file, I renamed it to SDC-DOS.101 and ran your
updater program...this worked fine.

So I currently have, 

run @3 (runs Canyon Climer)
run @4 (runs Don Pan)
run @5 (runs Mega Bug)
run @6 (runs Star Blaze)
run @7 (runs Thexder)

Thanks again Darren.

Cheers,
Shane




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