Anyone able to write serial PDA applications

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Nice one... what dev suite are you using?

MS eMbedded Visual C and Windows Mobile 2003 SDK with an emulator.

I managed to find an app yesterday called Commlog which is a serial monitor that runs on the PDA. I am now looking for a serial emulator that will allow me to play a capture back from the PC to the PDA, it would make development a lot easier.

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With my coding skills this could be a long project

I did a serial capture of the telemetry output on the AEM today and this should be pretty easy. The AEM supports upto 19 feeds for telemetry, for testing I have captured just 1 and 2 data feeds.

With 1 feed the stream length is 3 bytes, Header byte, stream data, checksum byte.

Here is a datastream for throttle position using 1 feed.

55 00 00 55 09 09 55 15 15 55 21 21 55 2E 2E 55 3D 3D 55 4D 4D 55 5E 5E 55 6D 6D 55 7E 7E 55 8F 8F 55 A0 A0 55 B0 B0 55 BC BC 55 C8 C8 55 D5 D5 55 E1 E1 55 EC EC 55 F7 F7 55 FF FF 55 FF FF

55 - header byte

?? - data

?? - checksum

All we have to do is convert the data byte into decimal and multiply by the scaler which for throttle % is 0.390625

09hex/09dec x 0.390625 = 3.52%

2Ehex/45dec x 0.390625 = 17.97%

6Dhex/109dec x 0.390625 = 42.58%

I will add the 2 feed datastream later

Are you doing this to provide additional in car monitoring tools for daily and track use? Seems a lot of work for development and tuning purposes where the aem software on a laptop would be usable. Would an in car double din PC with a dash mounted monitor not be a better solution for this application instead of trying to bodge up and mount a PDA? Guy I will shortly be working with again put a PC in his 300zx displaying alot of his ecu's outputs on an LCD screen that he configured himself.

Are you doing this to provide additional in car monitoring tools for daily and track use?

Yes

Its just a monitoring tool, the AEM gauge only shows one item at a time, with this I could do away with any additional gauges.

Having a PC in the car is not really an option.

A PDA connected directly to the ECU using the telemetry output would be ideal for my application.

Why is having a double din pc in your car not an option? You are bound to have a stereo in there right? Its only absorbing the same space as that. It can still play cds and be a radio (I think) and has an output to a screen. That for sure will provide a hell of a lot more scope than a fudged PDA application for 2003.

I dont have any stereo in it either

Good Work Wes

Geek

Ah ok lol so if it was IPOD plug in size then it'd be A ok lol:D

Ok back on topic

Here is a 2 feed data stream, the length is now 4 bytes, Header byte, stream data (2bytes), checksum byte. I am using batt volts for data field 1 and throttle % for data field 2.

55 B9 7E 37 55 B9 97 50 55 B9 B5 6E 55 B9 D2 8B 55 B9 ED A6 55 B9 FF B8 55 B9 FF B8 55 B9 FF B8

55 - header byte

?? - data - batt volts

?? - data - throttle %

?? - checksum

We convert the data byte into decimal and multiply by the scalers in the same way.

* batt v = 0.062500

* throttle % = 0.390625

The voltage is low as this was done with the engine off.

B9hex/185dec x 0.062500 = 11.56v

7Ehex/126dec x 0.390625 = 49.22%

The AEM supports 19 output channels which are configurable.

Now I just need to right an app to take this information and display it

Good Work Wes

 

Geek

Can someone not open up the aem software and get the parameters from there?

Yes you can access the parameters in the AEM software which only loads on a full blown PC not a PDA.

AEM wont release the serial datastream, I am using the serial gauge output for this.

I am looking for a PDA version of the gauge-tech unit, everyone thought they were a good idea

OK so thats no help in translating the parameters to a PDA application then? Would a program thats similar to the one I know a work chappy has in his 300zx for gauge displays help?

An example of what I plan to monitor

Engine Speed

Engine Load

Throttle

Air Temp

Coolant Temp

Injector Duty

Gear Calculated

Battery Volts

Ign Timing

Vehicle Speed

Run Time

Boost Target

Logging

O2 #1

O2 #2

O2 FB Status

Knock #1 Volts

Knock #2 Volts

EGT

The list to choose from is huge but once the app is done it just a matter of changing the scaler for that byte reference.

OK so thats no help in translating the parameters to a PDA application then? Would a program thats similar to the one I know a work chappy has in his 300zx for gauge displays help?

Not sure I know what you mean.

As I have done the serial trace and know how the datastream is assembled the info in the AEM application makes perfect sense. I dont forsee the need to do anymore serial captures to finish the app.

Nice work there Wez... seems that you are making quite good progress...

Although I'm working in VB, anything you need to ask, ask away..

When I'm on night's I'll be looking if I can get something to play the stream from a file on a PDA, will that be useful?

Also is the stream split at all, IE like a GPS stream into lines, or just one long stream?

PS, where did you get the scalers from?

Something that could play the stream out of a desktop serial into the PDA for testing would be great, there is some source code in this :

http://download.microsoft.com/download/1/3/d/13d9a962-d306-4130-bf63-298d0e032d3e/Serial_Comm_NETCF.msi

The stream is constant and the scalers are provided from within the AEM software.

A 2nd gen of this could even offer software based switches and functions to include uploading and downloading different maps etc.

I have an app ready to test now, just waiting for my serial cable to arrive

Oh yeah... will have to steal some time from the company tonight...

How did you get on?

My PDA serial cable arrived today, I have succesfully tested serial comms from my laptop to the PDA. I ran hyperterm on the laptop and Commlog on the pda which showed the data I was sending.

Just need to test it on the car now.

Hey buddy, back at work tonight..

Didn't managed to do anything last night, dratted work getting in the way. I'll see what I can do tonight.

PS... TBH doesn't look like there is much for me to do, you seem to have it all in hand...