LPCXpresso peripherals greyed out when debugging (LPC1769)

[lpcware]

Content originally posted in LPCWare by Petervg on Sat Jun 07 02:50:47 MST 2014
Hi,

I have a problem when trying to view the peripherals when debugging. To make sure this is not related to any hardware I made, i tried this on a standard LPCXpresso board with an LPC1769:

I started LPCXpresso in a new workspace, imported the cmsis libs, started a new project, compiled and started a debug session (no problems so far). However, when I select the "peripherals"  tab to view the registers associated with eg UART3, I noticed that a lot of peripherals (including UATR3) are greyed out. If I select UART3, I can only see the adress of the peripheral in the memory view, but no further details whatsoever. When I click on UART1 (not greyed out) I can see all registers fine.

I have tried this in LPCXpresso 6.1.4 build 194, LPCXpresso 7.0.2 build 102 and LPCXpresso 7.2.0 build 153.
Hardware used: LPCXpresso board: LPC1769 rev B.

Does anybody know why some peripherals are greyed out? I need to be able to view the registers of UART3 to debug a software issue in a project.

I have included screenshots to show the issue and also included the workspace I used when making the screenshots.

With kind regards
Peter

Original Attachment has been moved to: UARTtest.zip

[lpcware]

Content originally posted in LPCWare by Petervg on Sat Jun 07 14:29:31 MST 2014
hah.. you are spot on! Issue solved!
If the peripherals don't have a clock attached, they cannot communicate with anything. Adding the code below 'fixed' the issue.

LPC_SC->PCONP = LPC_SC->PCONP | (1<<25);

Thanks!!
Peter

[lpcware]

Content originally posted in LPCWare by TheFallGuy on Sat Jun 07 03:06:59 MST 2014
By default, some peripherals are disabled after reset. You have to enable them to be able to view the registers. Iirc uart1 is enabled, but uart3 is disabled. The tooltip on the peripheral will tell you it's state.