LPC MicrocontrollersのトピックLP1768 and external program memory

LP1768 and external program memory

lpcware — Wed, 15 Jun 2016 17:51:05 GMT

Content originally posted in LPCWare by rezaxyz on Sun Nov 01 11:56:14 MST 2015
Hi all,

I'm developing an application on LPC1768 which has many mathematical and memory consuming functions. Since the hardware is cost sensitive I can't port the firmware to devices with external memory interface (e.g. LPC1788 and LPC43xx). In your opinion is it practical using IAP or running functions from internal RAM? Is there any solution to overcome program memory limitation on LPC1768?

Thank in advance,
Reza

Re: LP1768 and external program memory

lpcware — Wed, 15 Jun 2016 17:51:06 GMT

Content originally posted in LPCWare by mc on Mon Nov 02 08:45:00 MST 2015
Hi Reza,
I think, if you are running out of program memory, RAM size and IAP functions may not help. Not sure how you are planning to use IAP to overcome program memory size. Are you aware of all APIs available in the ROM?
What functions are you planning to use from ROM?

Re: LP1768 and external program memory

lpcware — Wed, 15 Jun 2016 17:51:06 GMT

Content originally posted in LPCWare by rezaxyz on Tue Nov 03 03:00:03 MST 2015
Dear mc, thanks for your reply

Quote: mc

Not sure how you are planning to use IAP to overcome program memory size. Are you aware of all API available in the ROM?

Is it possible to store bulk functions in an external flash memory (like SPI NOR memories) and when each of them is necessary then program it to the internal flash at the run-time by IAP functions?
Alternatively due to endurance of flash memory, Can I loading functions from external memory to the internal SRAM and temporarily remap the memory to run that function?

Re: LP1768 and external program memory

lpcware — Wed, 15 Jun 2016 17:51:07 GMT

Content originally posted in LPCWare by rocketdawg on Tue Nov 03 08:19:45 MST 2015
I find the price difference betweem a 1768 and a 1788 as less than $2 in small quantities.
you will spend much more than $2 per part cooking up some scheme to work around this.

Be aware that internal flash has a erase cycle life. When it fails, you will have a warranty issue.