On Thursday 04 January 2007 19:27, polly wrote:
> Thanks for the snippet, Ernst, I've been trying to locate the
> descriptors in flash a la uChip Demo code rather than in RAM
> as your code seems to do.
>
> regards, p
Well, I keep the descriptors in flash. (note the "code" keyword)
I just don't care where in flash, thats for the linker to worry about.
When sending an descriptor, I copy it into my transfer buffer, simply with:
-------------
unsigned char * outputData;
unsigned int dataSize;
static void fill_ep0in_buffer(void) {
unsigned char i;
unsigned int bufferSize;
data unsigned char * dest;
// How much to write this round?
if(dataSize < EP0_SIZE)
bufferSize = dataSize;
else
bufferSize = EP0_SIZE;
// Load the high two bits of the byte count into BC8:BC9
EP0Buff_in.StatusBits.countHigh=(unsigned char)(bufferSize >> 8);
EP0Buff_in.count = (unsigned char)(bufferSize & 0xFF);
EP0Buff_in.ADDR = PTR16(&controlTransferBuffer);
// copy dest, source, bytes
dest=controlTransferBuffer;
for (i=0;i<bufferSize;i++) {
*dest++ = *outputData++;
}
// Update the number of bytes that still need to be sent. Getting
// all the data back to the host can take multiple transactions, so
// we need to track how far along we are.
dataSize -= bufferSize;
}
------------------------
where "outputData" is a global variable pointing to the data to send.
its a generic pointer (three bytes long) so "*outputData" invokes gptr_get,
and the function works transparently both with data from memory and flash.
/Ernst
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys - and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
Sdcc-user mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/sdcc-user
