he351ve can

[fpvmustang]

getting around 1 volt out of the ms3 .75 out of vgt both on voltage climbs to around 1.2
I followed wires from processor js6 js8 (been a few days not positive i remember numbers correctly) through spare 1,2 to vgt made sure can high low were not reversed.

I did not see where the 120 ohm termination resistor is on the 3.0 board.

I did not add a termination resistor to arduino can shield.

Then i rechecked high low with DMM.

I have arduino teed in through can shields db9.

[fpvmustang]

i keep thinking the problem is in the code. since I'm not the only one who couldn't get them to talk.

Maybe i should try to read can signal from ms3 with arduino?

[jsmcortina]

I'm not the only one who couldn't get them to talk.

Really?

This feature like many others seems to have suffered from a "drive by feature request." Someone asks for something, it gets added, then silence.

James

[fpvmustang]

http://www.msextra.com/forums/viewtopic ... ve#p457335

Well, after a few more hours of messing around, I have confirmed that the VGT actuator on my turbo works well. I used an Arduino and CAN-bus Shield with some simple code using a potentiometer to command position, and it works great. These vanes move really fast if you want them to!! They'll snap full open to full close in a fraction of a second!

So I know the issue is somewhere in the Megasquirt at least. With it currently working on the Arduino, worst case (i.e. I can't get MS to send the CAN signal) it will be very simple to use MSExtra boost control as a PWM input to the Arduino, which I can then send through the CAN-bus shield to the turbo. I might actually like that idea better, because I can set up a bunch of different algorithms that way. For example, set up a shaft speed control algorithm on the Arduino, but leave the PWM from MS hooked up, and switch between the two. Lots of possibilities now!

I need to look into CAN sensors to Arduino.

[fpvmustang]

I think everyone just gave up. without really trying. Some went to lil blackbox.
I know of 5 2.3 lima's running mega squirt with a he351ve but using pneumatic control. not to mention all the other engines out there.
The turbo's are still relatively cheap used on ebay.
I really think this will take off once we get it working.
I have 2 he351ve 1 he5?1ve all 3 have a home. once this works.

[jsmcortina]

So what exactly is different between the CAN messages sent from the MS3 and the Arduino code?

James

[fpvmustang]

I don't know what's different. I wish i did.

[jsmcortina]

Use a CAN scanner/sniffer and find out.

James

[fpvmustang]

ok I tomorrow off i'll do that.

the below code works good on arduino commanding 0-1000

Code: Select all

byte lo_byte = lowByte(Position);
byte hi_byte = highByte(Position);

byte data[] = { lo_byte, hi_byte, 0x01, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }; // data message with an added counter
//byte data[2] = {0x02, 0x00}; //for recalibrating gearbox
// Load message and send
CAN1.send (0x0CFFC600, extID, 8, data);
}

[Alfagta]

Maybe the cabus speed is your problem??

At the arduino code you start the canbus with 250 kbs, but ms runs with 500 kbs.

BR

[jsmcortina]

Maybe the cabus speed is your problem??

At the arduino code you start the canbus with 250 kbs, but ms runs with 500 kbs.

BR

That would certainly break it!!

Running the Megasquirt CANbus at 250k is possible, but would prevent communication with any Megasquirt compatible devices.

James

[fpvmustang]

well that would explain why ms3 kills my signal from the turbo to can sniffer.

[fpvmustang]

What's going on with using the other CAN ports on the ms3 processor?
What do i do to change the can bus speed to test this?

[jsmcortina]

What's going on with using the other CAN ports on the ms3 processor?

They aren't easily available. Even if they were, you'd need to write new CAN config and interrupt handlers to deal with them.

What do i do to change the can bus speed to test this?

Try changing

Code: Select all

CAN0CTL1 = 0xc0; /* BUSCLK (50MHz) */
CAN0BTR0 = 0xc4; /* SJW=4, prescaler = 5 */
CAN0BTR1 = 0x5c; /* Segment2 = 6, Segment1 = 13 */

To:

Code: Select all

CAN0CTL1 = 0xc0; /* BUSCLK (50MHz) */
CAN0BTR0 = 0xc9; /* SJW=4, prescaler = 10 */
CAN0BTR1 = 0x5c; /* Segment2 = 6, Segment1 = 13 */

Untested.

James

[fpvmustang]

Never tested slowing can bus speed. Went to Arduino control using boost duty.
http://www.msextra.com/forums/viewtopic ... 7&start=20

[jsmcortina]

I've re-added this for the next pre-1.5 firmware with support for 250k baud and the boost duty being sent in the first two bytes little endian.

James

[fpvmustang]

OK I'll test it when the alpha code is released.
something to think about currently I use a generic output to control vgt out of boost. To reduce lag.
In setup mode boost duty is sent all the time. I didn't need the generic output.
maybe a box to set turn on out put in kpa. Looks like now it's about 10 kpa below barometer.

probably guys will want a rolling anti lag input someday also. You know how these things snowball in to bigger projects.

[jacky4566]

For the guys using can bus. How did you tune the boost tables for cruise?
Wondering how to keep the vgt open if we cant set the closed loop boost target to a negative value?

[fpvmustang]

http://www.msextra.com/forums/viewtopic ... 01&t=60247
In closed loop out of boost the boost duty is zero full open vgt
I prefer for cruise around 550 vgt position