H743Zi2 Board

Author Message


Joined: 13/10/2014
Location: Australia
Posts: 715
Posted: 06:25am 27 Jun 2019      

Just got back and had a look at this in more detail, I've discovered something good and bad.

Turns out that the USB switch is not faulty - good but!

The Enable to the switch on the V1 board is taken HI to enable +5v USB out.

Then Enable on both V2 boards is not fully HI (floating around 1.7v) which could indicate an incorrect link setting? - BUT - it has to be taken LO to enable +5v USB, that is the opposite to the V1 board?

Without a circuit I can't go any further. I've still got it working but the timing of USB powerup (Enable line) is important to USB initialisation, sometimes it does not initialise but for the most it's ok.

Until I get a circuit and someone else tries a V2 with Keyboard I'm going to leave it at that.
It's all too hard.