Rev 3 Driver Board
On Wednesday morning Dave brought me this...
I was teaching on Wednesday afternoon, but on Thursday I was able to give it a thorough testing. The news is good. All the issues previously identified have been dealt with, one way or another. In the rev 2 board there were a few on-screen display menu settings not working properly. These have all been fixed now in rev 3. Two more little ones were found, and they will be fixed for production.
The hardware issue we had with rev 2 was voltage sag under load on the USB Pi Power port. This is no longer a problem when powered from the 12V input, and the bottom-left inductor no longer gets uncomfortably hot to touch.
The only remaining hardware issue is a slight voltage sag on the Pi Power Port when the whole thing is powered from the 5.2V input. So we've decided, rather than go through another driver board iteration, to simply supply a 5.5V, 2 Amp PSU with HDMIPi (for those rewards that included one, and people who added one) instead of the planned 5.2V, 2 Amp PSU. This compensates for the Voltage drop across the driver board and ensures an adequate Voltage gets to the Pi. Simple solution :) This is to try and make it bullet-proof.
Let me stress here, that, in testing, a good 5.2V, 2A micro-USB supply does work to power...
- HDMIPi screen
- driver board
- Raspberry Pi model B (rev 1 & rev 2 tested)
- Edimax wifi dongle
- Wireless keyboard dongle
- Pi camera shooting video
...but while shooting video, the Voltage across TP1 and TP2 on the Pi goes well below the 4.75V recommended by the Raspberry Pi Foundation.
By compensating for this at source, by supplying 5.5V in, we hope to pretty much eliminate this as a source of problems for end-users.
We could redo the power circuit on the driver board, but we know you don't want to wait an additional iteration's worth of time (6-8 weeks). We certainly don't either. It's time to get HDMIPi out to you lovely backers, who've been waiting so patiently and expectantly. This will get the job done and provide sufficient Voltage to reliably power the Pi.
You should all have received your surveys by now. ~80 people still haven't replied. If you backed through the KickStarter, and you haven't received a survey email, log into your KickStarter account and you can find it there. (If you pre-ordered through the Cyntech shop, you will have received a different email. The two systems are entirely separate.)
For those who were hanging back because we didn't show you the colour options, here is an idea of the colours. The pink colour is still not fixed, as the one we originally chose wasn't suitable. Not many people chose pink. Over half of you chose black.
Case Rev 3
Dave also brought me the latest case from Pimoroni. It's also at the 3rd iteration. There will be a thin bezel at the front. But if you prefer not to fit it, you can leave it out. Here's what it looks like for the moment. This is not the same blue as the blue we chose, it's what Paul had in stock to play with...
It's coming along nicely, and we're nearly there.
UNICEF Pi4L Project
In the previous update I mentioned that I'd be blogging about the UNICEF Lebanon project. I was deliberately a bit vague on that because I'd been asked to write a guest post for the Raspberry Pi Foundation's blog. That blog article, detailing the whole project, can be found here http://www.raspberrypi.org/unicef-educate-syrian-children-in-lebanon/
When Will I Get My HDMIPi?
We're hoping to go straight into production now. If all goes well, we hope to be able to ship within 4-6 weeks.
That's about it for now. We wish you a happy weekend.
Alex and Dave http://hdmipi.com @hdmipi