topic Re: Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly in LPC Microcontrollers

Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly

lpcware — Wed, 15 Jun 2016 20:16:57 GMT

Content originally posted in LPCWare by barts on Tue Jun 02 23:00:08 MST 2015
Hello,

I recently played with the LPC1549 LPCXpresso board, creating an application with LPCOpen. I had problems with what seemed an inaccurate or instable CPU clock frequency. After investigating it turned out that there's something wrong in Chip_SetupXtalClocking() in sysiniit_15xx.c.

/* Setup PLL for main oscillator rate (FCLKIN = 12MHz) * 6 = 72MHz
   MSEL = 5 (this is pre-decremented), PSEL = 1 (for P = 2)
   FCLKOUT = FCLKIN * (MSEL + 1) = 12MHz * 6 = 72MHz
   FCCO = FCLKOUT * 2 * P = 72MHz * 2 * 2 = 288MHz (within FCCO range) */
Chip_Clock_SetupSystemPLL(5, 2);

The comment states that the value 1 is passed as PSEL value, but the second argument of Chip_Clock_SetupSystemPLL() is actually 2 instead of 1. That causes the FCCO to be set at 576 MHz, way beyond the maximum of 320 MHz. Changing the argument to 1 fixed my problems.

Re: Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly

lpcware — Wed, 15 Jun 2016 20:16:58 GMT

Content originally posted in LPCWare by chrta on Sat Jun 06 01:05:57 MST 2015
Hi barts,

thanks for sharing this. The same bug is present in the same file in Chip_SetupIrcClocking().

Re: Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly

lpcware — Wed, 15 Jun 2016 20:16:58 GMT

Content originally posted in LPCWare by michaelkelley on Thu Jul 23 13:05:42 MST 2015
Nice catch!

I was having some bizarre intermittent issues in my LPC15xx part until I found this post. Making the suggested change seems to clear them up.

Thanks!

Re: Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly

lpcware — Wed, 15 Jun 2016 20:16:59 GMT

Content originally posted in LPCWare by mc on Thu Jul 23 17:40:22 MST 2015
Hi All,
Thanks for catching this bug. We will add it to tracker to fix in next s/w revision.

Re: Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly

lpcware — Wed, 15 Jun 2016 20:17:00 GMT

Content originally posted in LPCWare by miccio on Fri Feb 05 05:40:31 MST 2016
This bug has not been fixed with the latest release of LPCOpen (2.20)

And the always-mentioned bug tracker is pretty much empty https://www.lpcware.com/node/1107569/ct_plus

Re: Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly

lpcware — Wed, 15 Jun 2016 20:17:00 GMT

Content originally posted in LPCWare by NXP_Support on Fri Feb 05 10:26:00 MST 2016
Hi miccio (and LPC15xx users in general!),

Apologies to our LPC15xx customers on behalf of NXP Support. Acknowledging deficiencies has little meaning if action is not taken. The LPCOpen 2.20 release for LPC1500 was rushed to provide (overdue) CAN example fixes. The pressure to get the CAN examples released resulted in not reviewing the bug tracker for that release.

NXP is reviewing our LPCOpen releases per MCU family to prioritize update releases for the coming quarter, with the intention of addressing bug fixes.

Regarding the bug tracker - NXP maintains an internal bug tracker system. The LPCware.com public bug tracker was never adopted by our user community - bugs get reported on the forums instead. As a result the LPCware.com public bug tracker is likely to be phased out this year.

Best regards,
-NXP Support

Re: Bugreport: LPCOpen 2.08c for LPC15xx configures PLL incorrectly

lpcware — Wed, 15 Jun 2016 20:17:01 GMT

Content originally posted in LPCWare by mubes on Thu Apr 21 06:16:48 MST 2016
This was Feb, it's now April....bug still there, still 2.20 :-(

DAVE