BeagleBone AI

[Dr. Rolf Jansen]

> Am 31.05.2020 um 14:11 schrieb Ian Lepore <ian at freebsd.org>:
> 
> On Fri, 2020-05-29 at 23:21 -0300, Dr. Rolf Jansen wrote:
>> ...
>> 
>> First Question:
>> 
>> What modern SBC with more than 1 I²C bus and which can run FreeBSD 13++ would you suggest?
>> 
>> ...
>> 
>> Two more Questions:
>> 
>> Is it reasonable to assume that FreeBSD would run on a BBAI in the future, let’s say in 2 to 3 years?
>> 
>> Perhaps I could help porting FreeBSD to a BBAI. What would be the general steps?
>> 
>> 
>> Many thanks in advance for any suggestions, advices and clarifications.
>> 
>> Best regards
>> 
>> Rolf
> 
> BTW, if you need drivers for any new i2c devices just let me know and
> I'll see what I can do.

I am pretty comfortable with register level programming, and so far I came away with ioctl() calls for what I needed. So perhaps I won’t need exactly a driver for new I²C devices. However, I am far away from being a perfect I²C expert, specially when it comes to timing and the best sequence of addressing different devices on the bus. Perhaps, I may ask some questions when I run into problems.

> Also, in my experience you can often get away with running an i2c bus
> faster than 400khz if you need more bandwidth.  I've never seen any
> modern chip fail to work at 800khz, and most seem to work fine up to
> about 1mhz; above that they become pretty unreliable.

Does this „over clocking“ work for the ARM boards as well? I just set the clock-frequency in the dts-overlay which activates I2C1 of the BBB from 400000 to 800000. The bus seems to work as usual, however, I did not yet come to check its speed. How again would I do that? Probably there are many more questions to come :-)

Best regards

Rolf