Does anybody see an issue to make OSD using FEZ Domino/Cerb40?

I’ve found this project: Diy osd (Arduino and opensource) - RC Groups and was wondering if it is posible to make using FEZ boards. Why would I need that? Because on Arduino they are reaching limit of processing power as I understand, so it is hard to add new features, so I thought FEZ boards are much faster at least on spec sheet.

Depends on what you’re doing. Because the FEZ is running interpreted code, it has the potential to be much slower than an Arduino. On some things, it’s much faster, some things, much slower.

As I’ve mentioned it will be OSD, that means I need to get analog video signal, add to it osd information and return it as analog video output.

So, I read a bit further in the article, to see how this OSD was actually being done. Now that I know, I can tell you that it’s a non-starter. NETMF is not real time, and the extremely tight timings required do not fit well with the strengths of the NETMF platform. You could do it in RLP, but then, what would be the point of going with NETMF at all…

I would look at this project by Andrej

It will do what you want, but uses an OSD chip.

At $15-$20 per, using a MAX7456 means the project no longer uses “Simple and cheap hardware”, especially if Gadgeteer is involved.

… which isn’t one of the stated requirements :wink: (yet :slight_smile: ) But yes, an OSD chip will add to the cost.

@ Brett - May not be cheap, but I think I now have another project to add to my list for the spring.

This would go great with my R/C Super Cub…the next question would be how hard it would be to send the OSD info wirelessly to a head-mounted display. :slight_smile:

you should ping Andrejky @ work and see because IIRC he had his RC plane piping back FPV

well, $15 would be acceptable, but it is quite complex chip, so you need a board for it - which is complex and will be even more expensive than chip at single unit production :slight_smile:
there’s break out board - but it is 40$, so far I think it will be simpler and cheaper to connect FEZ to my GOSD II, just to have everything on one board would be much more convenient.

Thinking about RLP, may be it would be reasonable to call RLP function on new line interrupt, and all other code could be managed, may be that would make sense? Just I’m not sure if CERB40 supports RLP.

Edit: regarding RLP, I’ve remembered that it has quite much overhead, so it is not advisable to call it often, so on line interrupt call it would make no sense.

The Cerberus has RLP Light, which is RLP made even harder… :slight_smile:

But you can, via RLP install an interrupt to call some RLP code at the start of the interrupt. Don’t expect too much CPU time left over for NETMF if you want to “bitbang” OSD.

There is an excellent option in the same price range as the Gadgeteer VideoOut Module.
Check out the OSD module from Decade Engineering at DecEng which costs $90.
It has SPI and serial port interfaces. Just add Gadgeteer and video connectors.

This is at the top of my Gadgeteer todo list. I have all the parts. Just need to find the time.
I hope to make a PCB version after making a wire wrap prototype.
Thinking that GHI should team with Decade and make a Gadgeteer module.

I used a previous generation module, BOB-3, in a product for my job several years ago and it worked out great.

Using Propeller chip from parallax would be a better option at lower cost.

I have seen that Propeller has sample code for OSD, but the sample only supports NTSC.

I made a few boards with MAX7456 at work. The MAX7456 is a bit expensive, but it isnt $90. :slight_smile:

At work we might look further at a propeller based solution, if that project goes out of a “technology preview” stage.

If a 16 MHz AVR can bitbang OSD, then I suspect a 168 MHz ARM can bitbang it with LOTS of headroom left over…

Thanks everyone for answers, although still not sure - it is possible or not to implement that in FEZ board without additional boards/chips.
I think at the moment I’ll focus on using FEZ board only for processing sensors/transmitting telemetry, but if will find a free minute, I will definitely try if it is possible to do OSD on FEZ only.