[coreboot] Tester devices [was: QA contribution]

[Juhana Helovuo]

Hi Peter,

Peter Stuge wrote:
>> In this image you can see the tester plugged into an Asus mainboard:
>>
>> http://alpskari.asiantuntijat.org/~juhe/in-system-flasher/DSC08430.jpg
> 
> Sadly this URL does not work for me. :\

We have been suffering from a server crash, because of a power failure 
in our ISP's machine room. This particular server did not start after 
power was restored. It has also hampered my email access.

Now that server is back online and works at least for me.


>> I do not know if it is possible to implement two USB CDC class
>> virtual serial ports with less than seven EPs. With two serial
>> ports, one could represent the RS-232 interface, and other be used
>> to control the programmer without writing any custom USB drivers.
> 
> I thought we agreed that in particular the flash programming must be
> implemented with a custom protocol directly on top of USB, rather
> than something on top of a serial port emulation on top of USB.

You are right, serial port on top of USB is not a good final design.

I wrote the first version with serial port emulation, because that was 
the quickest way to see that all the hardware parts work, and the whole 
concept is usable at all.

Now that I have seen the hardware working, it is a good time to design a 
better protocol on top of USB.


> Ideally data can be buffered as well. How much RAM is available in
> the AT90USB you are using?

There is 512 bytes RAM available. Additionally, there is 176 bytes USB 
packet buffer RAM in the USB controller.


Best regards,
Juhana Helovuo