RS-232 interface specification / Power

[fergusd]

Hi, just bought an older PDR-100 (pre g-sensor build), very pleased with it so far, am interested, however, in possibilities using the RS-232 data input into the device.

Is there a data specification for this interface available ?

You mention elsewhere that data can be sent to the PDR-100 and then parsed and overlaid on the video, is this a specific forward looking idea or is something in place now ?

I'd like to be able to send my PDR an RS-232 data stream with RPM and Speed data in it and have it overlayed on the video, I can quite simply deal with generating this data stream and complying with any data format required (atmel avr hacker), so . . . what is possible ?

Secondly a question on power. If I have 4 nimh cells fitted in the device and a pack of 8 nimh in a cell holder plugged into the external 12V dc jack . . . what order will the device use the cells, I assume external then internal, however, it may be that in some of my testing the internal cells were not used when the external jack was plugged in . . . can you confirm the intended mode of operation ?

Thanks for your help.

Fergus Duncan
Hillclimber

[RandallNoll]

Fergus,

I'll let Randy discuss the data overlay piece. The short answer is the unit will require customization to do this. We currently do this with Motec, where the Motec data is overlayed on the video. This is a $300 upgrade. I would assume a custom upgrade for a one-off application would be substantially more.

Regarding power, the unit will use the external power first, then fail-over to the internal batteries when the external voltage drops below the minimum required.

Thanks!

[Mark]

If you just want to do an on screen display, there are a few products on the market to do that kind of stuff.

Me, I used the HITT Consulting OSD. Their web site is down right now but Google's cache of their web page says that they've stopped selling products as of April first. However I note that Sparkfun has a few of the boards still in stock. I also have the schematic and code if you want it if the HITT site is still/permanantly down.

Heck, you can make an OSD of your own with the schematic for a lot cheaper (no copyright posted on the schematic, though the code says "free for non-commercial use").

This is what I did after buying the HITT board to see that it worked well enough for my purposes- I used a propeller protoyping board (that's the processor in it- a Parallax propeller) and made my own OSD. I haven't gotten around to laying out a new board since the proto board works well enough.

I admit, my board is a rat's nest of wires since I pass not only the video through it, but also the RJ-45 digital interface (to turn on the PDR) and the power and added a connector for my GPS receiver.

Font size and pixel resolution is limited because of the propeller's RAM and the overlay isn't completely opaque (probably due to a difference in the peak to peak voltages between the propeller and the camera signal).

Yes, I'd also much prefer being able to send serial commands directly to the PRD to do the on screen display, but if it's going to be significantly more than $300, then I'll make do with the setup I have.

Then again, if you want to split the costs of getting custom firmware made for the PDR, depending on the price, I might be willing to pitch in for it.

[fergusd]

Ok, that's a shame, I'd have thought that sort of interface could be generic and reusable, no matter it's certainly much cheaper to DIY and make an external box to do it, a very quick google shows up the BOB-4H overlay development kit which is in production and available in the uk/us at a reasonable price, so that's the way I'll likely go.

Thanks

Fd

[BroussalM]

Hi Fergus,

"I'd like to be able to send my PDR an RS-232 data stream with RPM and Speed data in it and have it overlayed on the video, I can quite simply deal with generating this data stream and complying with any data format required (atmel avr hacker), so . . . what is possible ?"

Instead of having some curves overlayed permanently on the video and with simple shape, why don't you try to do that with Dashware?

Cheers
Michel Broussal

[fergusd]

Well I'm not really interested in pretty looking gauges, a very simple textual representation of the data I'm after on the video is more than adequate . . . I have specific reference points which I can visually see and given the frame counter overlay I can use that to produce as many splits as I need for reasonably detailed analysis, given a burned DVD with single frame advance and a spreadsheet ;-) . . . couple that with the fact that I value a new set of tyres more than a datalogging dash . . . and I think the video solution gives me just about everything I want . . .

This is the kind of thing I will be recording . . . the footage some old camcorder footage we shot a few years ago, the camcorders, however, die with the vibration, hence a solid state solution :

http://www.youtube.com/watch?v=0XAn0lPXxDw

Fd

[BroussalM]

Hy Fergus

I didn't know you could drive a race car so fast on a cycle path ...
Oupss, not very "sexy" the right curve just at the bottom of the hill !
But realy, If you stop to buy your set of tyres for 149 $, they'll give you a road more largeur for your races, sure! :rolleyes:

Of course I understand what you mean.

Just a thing where Dashware help me when I'm in a race week-end:
The possibility to compare the datas of two or three practices on one video footage to see exactly the moment where I gain or lose time.
The small 0.2" that you need to win the race are suddenly evident .
And you'll can make very simple gauges (or awful,as you want... ) to see that.
It's something not easy to see with the datas overlayed on each video.

Good races
Michel Broussal