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Problem with EB40A derived board, change in clock frequency


Greetings.

I have run eCos 2.0 successfully on an eb40a derived board using the eCos
template for the eb40a. I could run all the relevant tests and view
diagnostics on the serial port configured by default at 38400 baud.

Now, for some reason unbeknownst to me, the hardware has been modified such
that the external master clock being fed to the microcontroller is now at 40
Mhz as opposed to the original 66Mhz.

In this situation, I can determine, using a Wiggler over JTAG, that eCos is
in fact running. However I do not see any diagnostic outputs on the serial
port.

I am aware that the change in the external master clock does in fact need to
reflected in the CDLs such that eCos is aware of the same and can provide
gauranteed delays etc with the new clock. 

I need to know the sequence of changes to be made in the eCos repository,
including the CDLs etc to ensure that eCos can work with the new clock and
the serial diagnostics work at a specified baudrate (38400 would do).

I seem to think that the following would need to be redefined:
1. CYGNUM_HAL_RTC_NUMERATOR
2. CYGNUM_HAL_RTC_DENOMINATOR
3. CYGNUM_HAL_RTC_PERIOD

The above will need to be defined to ensure that the timeslice remains at
100Hz (I'm assuming that this is the default).

What should be changed in order for the USART to work at any standard baud ?

The other question I have is that for my application, I need to run eCos
from FLASH which means that gdb over JTAG should support hardware
breakpoints. Is this possible, for the AT91FR4008 processor ?

Any help would be much appreciated.
Thanks and regards,
Robin


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