topic How to restore PIO1_3 reset value? in LPC Microcontrollers

How to restore PIO1_3 reset value?

lpcware — Wed, 15 Jun 2016 19:27:30 GMT

Content originally posted in LPCWare by yuezhang on Fri May 16 11:18:46 MST 2014
I used PIO1_3 on LPC1111 as SWDIO for debugging all the time, until I changed the pin function in my program by mistake. I changed it to GPIO. The problem is after I re-power the board, the SWDIO stil doesn't function. I can't use the SWIO for debugging anymore. But as its datasheet mentioned IOCON_SWDIO_PIO_3[FUNC] should be 0x0 after reset. Any way to fix it? Thanks.

Re: How to restore PIO1_3 reset value?

lpcware — Wed, 15 Jun 2016 19:27:31 GMT

Content originally posted in LPCWare by R2D2 on Fri May 16 11:52:46 MST 2014

Quote: yuezhang
But as its datasheet mentioned IOCON_SWDIO_PIO_3[FUNC] should be 0x0 after reset. Any way to fix it?

Yes, but if your 'wrong' program is executed, SWDIO is GPIO again :)

So the solution is not to run your program. If you 'Boot into ISP', bootloader is executed and it's not switching pin function to GPIO.

See: http://www.lpcware.com/content/faq/lpcxpresso/regaining-debug-access

That's the solution...

Re: How to restore PIO1_3 reset value?

lpcware — Wed, 15 Jun 2016 19:27:32 GMT

Content originally posted in LPCWare by yuezhang on Fri May 16 14:16:59 MST 2014
Thanks.