BeagleBoard DPMS

I am trying to enable monitor low power modes
I have found the following commands :-

void HAL_Video_SetBlank(uint blank, uint DPMS)
which does what I think I need, I have tried calling this from BASIC, but with no success.

I have also found
void HAL_Video_SetBlank(uint powersave) I am not sure if I need to issue this first.

The DMPS screen saver works from the desktop, so I assume it must be possible.
Anyone got any ideas? TIA

You’ll want to use the GraphicsV “Set blank” call (R4=4).

The reason for this is that there are two ways video drivers can be implemented in RISC OS 5 – they can be implemented as a module that responds to the GraphicsV vector, or they can be implemented in the HAL (using the HAL video calls which you’ve found). The kernel is actually the default GraphicsV claimant, and contains code to forward the request to the HAL if no module has responded to it. So RISC OS software which needs to interact with the video driver on a lower level than the existing SWIs allow should always use GraphicsV, and let the kernel worry about forwarding the requests to the HAL if necessary.

On the beagleboard the OMAPVideo module is the (GraphicsV-based) video driver, so apart from a couple of the HAL calls which the kernel relies on during startup, none of the HAL video calls are implemented.