LPCOpen v2.10 Brown Out Detect (BOD) issues for LPC40xx

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

LPCOpen v2.10 Brown Out Detect (BOD) issues for LPC40xx

1,156 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by AndyMcC on Fri Dec 12 03:06:27 MST 2014
The LPCOpen v2.10 release notes for the LPC17xx/LCP40xx at http://www.lpcware.com/content/project/lpcopen-software-development-platform-nxp-lpc-microcontroller... state:

Quote:
Known issues (Carry-Over)
•The BOD (Brown Out Detector) example doesn’t seem to work on the LPC1788 and LPC408.


The header file: sysctl_17xx_40xx.h has the inline functions: Chip_SYSCTL_EnableBOD(), Chip_SYSCTL_DisableBOD(), Chip_SYSCTL_EnableBODReset() and Chip_SYSCTL_DisableBODReset(), which contain bit polarity errors in that bits are set when they should be cleared and vice versa.

From the LPC 407x/408x user manual (UM10562), section 3.3.2.1 Power Mode Control register:

Quote:
3 BOGD Brown-Out Global Disable.
When BOGD is 1, the Brown-Out Detect circuitry is fully disabled at all times, and does not consume power.
When BOGD is 0, the Brown-Out Detect circuitry is enabled.
See the System Control Block chapter for details of Brown-Out detection.
Note: the Brown-Out Reset Disable (BORD, in this register) and the Brown-Out Interrupt (see Section 5.1) must be disabled when software changes the value of this bit.

4 BORD Brown-Out Reset Disable.
When BORD is 1, the BOD will not reset the device when the VDD(REG)(3V3) voltage dips goes below the BOD reset trip level. The Brown-Out interrupt is not affected.
When BORD is 0, the BOD reset is enabled.
See the Section 3.6 for details of Brown-Out detection.


The attached file has corrected, commented versions of these inline functions.

Original Attachment has been moved to: sysctl_17xx_40xx_awm.h.zip

Labels (1)
0 Kudos
1 Reply

579 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by NXP_Support on Mon Dec 15 19:01:00 MST 2014
Thank you AndyMcC!
We logged this to be corrected in the next LPC17xx/40xx release update.
-NXP Support
0 Kudos