Comments on: 3rd UHK post-campaign update: The new firmware is in great shape!

By: edbo

edbo — Sat, 16 Apr 2016 10:53:43 +0000

In reply to László Monda. Thanks for the update.

By: László Monda

László Monda — Sat, 16 Apr 2016 09:56:33 +0000

In reply to edbo. Very good point, Edbo. The maximum cable length is indeed shorter due to the capacitance of the I2C bus. But I tested I2C communication between the halves a couple of weeks ago with a 20 meter long cable and it worked at 100K baud. The plan is that if communication gets unreliable because of external noise then the baud rate will be throttled by the master (which is the right keyboard half). We can detect this condition by using checksums. The throttled baud rate shouldn't effect user experience in any major ways, possibly apart from competitive gaming, where folks will hardly ever use a 20 meter long cable.

By: edbo

edbo — Sat, 16 Apr 2016 09:46:09 +0000

I'm just curious, but is it still possible to use a long (10 meters) cable between the two halves? and am I still be able to change the length of the cable? From my own experience with using I2C I walked into trouble with replacing a short (10 cm) cable with a longer (20 cm) cable. But now you want to replace a 20 cm? cable with a 10 meter cable.

By: László Monda

László Monda — Thu, 07 Apr 2016 19:40:03 +0000

In reply to Cedrick. Hi Cedrick! The planned security modes are unchanged despite the change in processor. As for locking the flash with lock bits I'm not sure whether that's possible because I'm not an ARM expert, but I wouldn't consider it a good practice because it would make the firmware of the UHK non-upgradable.

By: Cedrick

Cedrick — Thu, 07 Apr 2016 18:05:43 +0000

Has the change in processor affected the security locking bits?

By: László Monda

László Monda — Wed, 30 Mar 2016 19:46:17 +0000

In reply to Adam. Thanks for reading, Adam!

By: Adam

Adam — Wed, 30 Mar 2016 19:43:37 +0000

Thank you for the update!