STM CircleOS forum / CPU Freq.

sjoerd · 2009-02-07 22:58:15

Known issue: Because the USB uses a modified clock configuration, changing the CPU freq from the OS menu will cause the USB MS to stop working..

Last edited by sjoerd (2009-02-07 22:58:31)

Francis · 2009-02-09 13:09:30

You can see in CircleOS how we manage the frequency changes 9at least the period). See the macro 'WEIGHTED_TIME'.

I was wondering whether it would be interesting to integrate the 'USB mass storage' in CircleOS (in the non-debuggable area). Just to make things easier. Because we can dynamically redirect the irq, it would not be a problem for other USB applications, and 'nass-storage' looks to be the best 'default' candidate for the handling of the USB port.

sjoerd · 2009-02-09 13:54:47

I think it's a good idea to integrate USB mass storage into CircleOs.
Check the zip in the USB MS 1.1 project for my attempt to do so. There it's already part of the non debuggable area.
Besides the possibility to redirect the irq depending on the activated USB usage (audio, HID, etc), there should also be a protection that when USB mass storage is enabled, the internal filesystem should be readonly or perhaps disabled.

Francis · 2009-02-09 16:31:21

You are right... we should add a kind of semaphore to manage the access of the SD card.

# 1 2009-02-07 22:58:15 CPU Freq.

CPU Freq.

# 2 2009-02-09 13:09:30 CPU Freq.

Re: CPU Freq.

# 3 2009-02-09 13:54:47 CPU Freq.

Re: CPU Freq.

# 4 2009-02-09 16:31:21 CPU Freq.

Re: CPU Freq.

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