topic Re: Problem Booting from internal Flash on LPC1857 in LPC Microcontrollers

Problem Booting from internal Flash on LPC1857

lpcware — Wed, 15 Jun 2016 18:17:51 GMT

Content originally posted in LPCWare by studyembedded on Wed Feb 18 22:33:17 MST 2015
Hi Friends,

I am working on LPC1857 on a customized board. I am very much confused about Boot mode. In this board boot pin P2_7 is samples low on reset, so boot source is determined by the states of pins P2_9, P2_8, P1_2, and P1_1. In User Manual page number 35 different boot modes are discussed, I have attached this page with post.

If you check there are options to boot from USART, SPIFI, EMC, and USB etc. But no option provided to boot from internal 512k bank A or bank B.

May be I am really dumb to understand it. Please guide me how to boot it from internal flash banks; I am able to dump the code in internal flash. But code is running from SPIFI. I need to change this and make it run from internal Flash.

Thank you.

Re: Problem Booting from internal Flash on LPC1857

lpcware — Wed, 15 Jun 2016 18:17:52 GMT

Content originally posted in LPCWare by starblue on Thu Feb 19 02:00:35 MST 2015
"Parts with flash boot from on-chip flash if PIO2_7 is sampled HIGH. See Figure 13."

That sentence is from the User Manual for the very similar LPC43xx, but it is missing in the UM for LPC18xx. The figure exists, it is figure 10 on page 38.

So you'll need to modify your board so that P2_7 samples high.

Re: Problem Booting from internal Flash on LPC1857

lpcware — Wed, 15 Jun 2016 18:17:53 GMT

Content originally posted in LPCWare by studyembedded on Thu Feb 19 03:27:10 MST 2015
Thanks starblue...i am downloading LPC43xx User Manual ....will go through it ....thanks!

Re: Problem Booting from internal Flash on LPC1857

lpcware — Wed, 15 Jun 2016 18:17:53 GMT

Content originally posted in LPCWare by studyembedded on Thu Feb 26 22:42:01 MST 2015
Hi...sorry for delayed reply as i was on a business trip ....could not make it. On my board P2_7 is connected to reset which is always going to be high..still not getting how to boot from internal flash(from bank A or Bank B).

Please help...Thanks.

Re: Problem Booting from internal Flash on LPC1857

lpcware — Wed, 15 Jun 2016 18:17:54 GMT

Content originally posted in LPCWare by embd02161991 on Fri Feb 27 16:34:07 MST 2015
Hi,

Parts with flash boot from internal flash by default. If ISP pin is high and BankA has a valid image, the code executes from BankA. If Bank A and BankB are empty, then the boot pins are checked. The "Boot process flowchart" in BootROM chapter of the User Manual has this information.
Hope this helps.

Thanks,
NXP Technical Support