Reading USB VBSTS bit of INTSTS0 Register with JLinkE

Hi,

 

For the purpose of showing that VBSTS changes when turning on or off the USB power on a custom board,

When using either JLinkCommander, JLinkExe, devmem, or md I am not able to read the USB registers (and also other system registers) of the RZ/A1

 

It appears that read access is blocked (values of 0 are returned)

For example

J-Link>mem 0x8010040 16
08010040 = 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
08010050 = 00 00 00 00 00 00

 

In e2 studio I am able to read some of the values as shown in the image below, though I am not entirely sure how to set a port as output to enable usb power in the custom board so it would be prefrable to be able to read the VBSTS register from within e linux.

 

 

Is there a setting to enable read access of the system registers?

 

Thanks,

 

Chris