topic LPC43xx CRP1 - USB ROM ISP in LPC Microcontrollers

LPC43xx CRP1 - USB ROM ISP

lpcware — Wed, 15 Jun 2016 18:35:52 GMT

Content originally posted in LPCWare by emh203 on Mon Jul 20 08:57:41 MST 2015

I wanted to make sure that if CRP1 is enabled, that I can still do a full erase via ISP over USB0.

The comments in "CRP.h" indicate that you can only do ISP full erase operations via the UART interface.

Re: LPC43xx CRP1 - USB ROM ISP

lpcware — Wed, 15 Jun 2016 18:35:53 GMT

Content originally posted in LPCWare by lpcxpresso-support on Mon Jul 20 09:05:28 MST 2015
The comments in crp.h pre-date LPC43xx. You should always read the User Manual to determine the exact meaning of CRP for your chip.

We will take a look at making the comments in crp.h more generic.

Re: LPC43xx CRP1 - USB ROM ISP

lpcware — Wed, 15 Jun 2016 18:35:54 GMT

Content originally posted in LPCWare by emh203 on Fri Jul 24 08:32:04 MST 2015
I did 1st look at the manual (UM10503 V1.8 for the LPC43 series). It makes reference to the IAP commands being disabled. It sounded like the hardware interface didn't matter (USB vs serial). The comment in the CRP.h then lead me to think that it did. I just wanted to make sure.

Re: LPC43xx CRP1 - USB ROM ISP

lpcware — Wed, 15 Jun 2016 18:35:54 GMT

Content originally posted in LPCWare by emh203 on Sat Aug 01 12:10:44 MST 2015
Ok....

I just verified that CRP1 does in fact lock you out from ISP operations over USB. Once I enabled CRP1, I could no longer connect via the DFU Programming tool. It does appear that I can still get into the ROM bootloader, it just does not appear to want jump into USB mode.

Prior to enabling CRP1, the USB ISP worked fine.

Also, I hacked in a connection to UART0 on P2_0 and P2_1. I was able to erase the flash can recover.

I believe the documentation needs updated to reflect that when CRP1 is enable, the boot source pins are not obersved. It appears that the only way to get in is via UART0.