OpenOCD Config - Memory Options for LPC2103?

Development Boards MicroMod
1

Greetings:

I am trying to write a config file that matches the LPC2103 and have found the following options are accepted by OpenOCD:

RAM-options LPC2103

working_area <target#> <‘backup’|‘nobackup’>

working_area 0 0x40000000 0x2000 nobackup

FLASH-options LPC2103

LPC2103 @ 19.6608MHz / 32K FLASH – 0x8000 from 32*1024 of FLASH

flash bank lpc2000 0 0 <target#> [‘calc_checkksum’]

flash bank lpc2000 0x0 0x08000 0 0 lpc2000_v2 0 19661 calc_checksum

I have two questions:

  1. Should one use the crystal frequency or the PLL multiplied frequency. In my case the core is running at 3 x Xtal = 58.9824 MHz. Should I use 58982 for the frequency? What is the significance of this setting? Is it critical for proper OpenOCD operation?

  2. The instructions suggest that all LPC210x devices are v1 type however when I tried lpc2000_v1 I got a “memory bank size bug” error from OpenOCD. Is it OK to use the v2 option for an LPC2103 device? How does an incorrect v type setting affect the debug performance? Would it simply not work or does it result in “flakey” operation?

Many thanks in advance for any help!

2
  1. Should one use the crystal frequency or the PLL multiplied frequency. In my case the core is running at 3 x Xtal = 58.9824 MHz. Should I use 58982 for the frequency? What is the significance of this setting? Is it critical for proper OpenOCD operation?
You have to specify the frequency your target will be running at when you're flashing it. If you know the PLL is working use the 58 MHz, otherwise use the crystal frequency. This value is passed as-is to the IAP call. Normally a wrong value works just fine, but you should try your best to specify the correct value...

The instructions suggest that all LPC210x devices are v1 type however when I tried lpc2000_v1 I got a “memory bank size bug” error from OpenOCD. Is it OK to use the v2 option for an LPC2103 device? How does an incorrect v type setting affect the debug performance? Would it simply not work or does it result in “flakey” operation?

Sorry, the documentation is incomplete here. The LPC210[123] use the v2 sector layout, too.

Regards,

Dominic

3

Greetings Dominic:

Many thanks for your reply but most of all many thanks for all your fantastic work on OpenOCD!

I replied earlier but my message never appeared on the board. Unless there is a delay it seems it got lost in cyberspace. I hope this doesn’t turn out to be a duplicate.

  1. It is my understanding that the PLL initialization is done by the firmware application thus at the time of FLASH programming I think the MPU is just running directly from the 19.6608 MHz oscillator thus I will leave the setting at 19661 and see if it works OK.

  2. It must be very difficult to keep documentation up to date considering the rapid introduction of new MPUs. It is great that OpenOCD detected and flagged that there was a problem with the v1 setting otherwise I would not have become aware that my settings were wrong.

Thanks again!

Best Regards,

Thomas M. Alldread