AM1808: Software ID of device clock rating

TommyG

Other Parts Discussed in Thread: LINUXEZSDK-SITARA, AM1808

Can I determine from software whether device is 375 MHz or 456 MHz device? I want to be able to use either device from the same software base and need to know which I am working with. I know you can determine the PG from ID register, but what about max CPU frequency?

Thanks.

over 14 years ago

0 melissaw over 14 years ago

TI__Genius 15940 points

Hi Tommy,

If you are using a Linux environment, one way to identify the max CPU frequency at run time is through the following command:

vi /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq

Note, the AM1x SDK with Linux kernel and file system is available at http://focus.ti.com/docs/toolsw/folders/print/linuxezsdk-sitara.html.

Regards,

Melissa

0 TommyG over 14 years ago in reply to melissaw

TI__Genius 13045 points

Melissa,

This looks like a pre-programmed value and not something that can identify which device is being used. Is this a correct understanding? I need something that can differentiate between 375 Mhz and 456 MHz devices at run-time with no pre-knowledge of which device is being used.

Thanks.

0 jc-ti over 14 years ago in reply to TommyG

TI__Mastermind 27585 points

Can you provide me the part numbers and package markings for both 375 and 456 MHz devices? It might be the case that there are no internally readable registers to differentiate.

Jeff

0 Mukul Bhatnagar over 14 years ago in reply to jc-ti

TI__Guru* 84375 points

Hi Tom

There is no way to distinguish the speed grade in software. The difference is only in the case marking/orderable parts.

Regards

Mukul

0 melissaw over 14 years ago in reply to Mukul Bhatnagar

TI__Genius 15940 points

Hi Tom,

Note the speed grade and PG revision of the AM1808 devices can be determined by the part number itself based on the nomenclature specified in the datasheet at http://www.ti.com/lit/gpn/am1808. On the AM1808 package markings, the speed grade is the number following "G1".

Regards,

Melissa

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AM1808: Software ID of device clock rating