|
Hi, all. I am attempting to conneect external flash memory to my C5410. The trouble is, I can't seem to read from it or write to it. It is supposed to be mapped to data memory. When I write to an address over 8000h, It doesn't change anything in the memory window (in Code Composer Studio). Basically, I need help setting up for external memory access. I have DROM=0, OVLY=0, MP/MC=1. Any help I can get would be greatly appreciated. If anyone is currently using external memory with their 54x, I would certainly like to hear about it. Thanks in advance for your help, Leigh W. Wells Electrical Engineer Acoustic Positioning Research (780) 439-1964 |
|
|
'5410 external mem access
Started by ●October 18, 1999
Reply by ●October 18, 19991999-10-18
|
Leigh, In order to write to Flash memory, you have to write a special sequence to do it. Also, you can't write a value from a 0 to a 1. You have to erase the Flash first which requires a different command sequence to the Flash. TI has an app note on their web site that shows how to do this somewhere. Look for the keyword Flash (something like interfacing the DSK to Flash memory). Also, I would recommend you pull down the data sheet for the Flash memory from the vendor's web site. You can't just write to Flash from the debugger and modify it. It isn't the same as RAM. Regards, Brian "Leigh W. Wells" wrote: > Hi, all. > > I am attempting to conneect external flash memory to my C5410. The > trouble is, I can't seem to read from it or write to it. It is supposed > to be mapped to data memory. When I write to an address over 8000h, It > doesn't change anything in the memory window (in Code Composer Studio). > Basically, I need help setting up for external memory access. I have > DROM=0, OVLY=0, MP/MC=1. Any help I can get would be greatly > appreciated. If anyone is currently using external memory with their > 54x, I would certainly like to hear about it. > > Thanks in advance for your help, > > Leigh W. Wells > Electrical Engineer > Acoustic Positioning Research > (780) 439-1964 > |
Reply by ●October 18, 19991999-10-18
|
Leigh, We are using externally connected flash memory to a 5410. The memory is mapped to the I/O space. Flash memory can not be used like regular memory, you need to, 1. Erase the whole block before you can write to it 2. Write is on a page (usually 512 bytes) basis 3. You need to sent control signals to the flash memory before it can be properly accessed. Hope this helps. -Alan At 05:05 PM 10/17/99 -0700, you wrote: >Hi, all. > >I am attempting to conneect external flash memory to my C5410. The >trouble is, I can't seem to read from it or write to it. It is supposed >to be mapped to data memory. When I write to an address over 8000h, It >doesn't change anything in the memory window (in Code Composer Studio). >Basically, I need help setting up for external memory access. I have >DROM=0, OVLY=0, MP/MC=1. Any help I can get would be greatly >appreciated. If anyone is currently using external memory with their >54x, I would certainly like to hear about it. > >Thanks in advance for your help, > >Leigh W. Wells >Electrical Engineer >Acoustic Positioning Research >(780) 439-1964 > > > |
Reply by ●October 18, 19991999-10-18
|
Leigh - As others have mentioned, you usually need special sequences to be able to write to flash memory. Those sequences and the rules about how the flash is organized (sectors, etc) vary from flash to flash. What type of flash part are you using? Most flash memories come erased, and the erased value is usually all bits set high (every byte is 0xFF, or more relevant to the C54x, all words will appear as 0xFFFF). When you read the flash, are all the words showing up as 0xFFFF? If they are, then that might at least indicate that you can read the flash. Kevin -- Kevin J. Neden Software Designer Transmission Elements Dept., JDS Uniphase Corp. "Leigh W. Wells" <> on 99-10-17 08:05:39 PM Please respond to To: "" <> cc: (bcc: Kevin Neden/HQ/JDS FITEL Inc) Subject: [c54x] '5410 external mem access Hi, all. I am attempting to conneect external flash memory to my C5410. The trouble is, I can't seem to read from it or write to it. It is supposed to be mapped to data memory. When I write to an address over 8000h, It doesn't change anything in the memory window (in Code Composer Studio). Basically, I need help setting up for external memory access. I have DROM=0, OVLY=0, MP/MC=1. Any help I can get would be greatly appreciated. If anyone is currently using external memory with their 54x, I would certainly like to hear about it. Thanks in advance for your help, Leigh W. Wells Electrical Engineer Acoustic Positioning Research (780) 439-1964 |
