Trying to connect via Bluetooth.

General Topics for configuring, operating and tuning the Megajolt. Also see the <a href="http://www.autosportlabs.net/MJLJ_V4_Operation_Guide">Operation Guide</a>

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bobclevenger
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Post by bobclevenger »

Yes, Brent, it works perfectly when hard wired either through a serial cable to an RS-232 port on my Panasonic CF-30 Mk3 or through a USB-to-serial adapter connected to the Lenovo tablet. It simply does not want to talk via BT. I am using the Panasonic for testing since it is easier to configure and is a more stable platform. Oh, I am not leaving the serial cable connected when trying to use the BT connection, nor am I leaving the BT module connected when using the hard-wired connection. Just in case you wondered.
...Bob

bobclevenger
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Post by bobclevenger »

Hey Brent, do you know of an alternate location to connect to the TTL-serial signal other than at the pins on the chip? I have managed to mess up those pins to a certain degree by soldering and unsoldering repeatedly. The circuit to the converter chip is good, since the unit communicates via the RS-232 port. It is just very difficult to solder to what's left of the pins and I may have a bad connection there. I'd like to try connecting elsewhere (at the other end of the wire, so to speak). Perhaps at the output of the logic chip rather than at the input to the level converter.
...Bob

bobclevenger
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Post by bobclevenger »

OK -- disregard previous request -- it would be good to know that, but I don't need it now since the mjlj module is talking to my laptop just fine now! During one of the "solder and resolder" periods I had managed to get the txd line switched with the rxd line. It really doesn't like that. I would recommend that anyone doing this use wires with individual connectors for the BT module pins. That way you can swap them out without resoldering if they get connected wrong.

Here are three photos of my board connected to the BT module.

Image
The Yellow and Orange wires are connected to the TXD and RXD connections (respectively) at the BT module; they are also connected to pins 11 and 12 of the MAX232A chip. Pin 11 is the third one from your left on the bottom row as you look at the photo. Pin 12 is the fourth one from the left on the bottom row (again, as you look at the photo).
So, Orange connects to pin 11 on the MAX232A chip (I know it kind of looks like it might be connected to pin 10, but it's not) and to RXD on the BT module. Yellow connects to pin 12 on the MAX232A chip and to TXD on the BT module. The Red wire connects to the positive 5 volt power right there on the MAP sensor and the Brown wire connects to ground right next to it. I do not have the TPS option, so I don't know how to hook up the power if that's what you have. Obviously the actual colours don't matter, that's just what I used.

A note on pin numbers on that MAX232A chip. Look at the chip so that the little dimple is at the top left of the chip. Pin 1 is right next to the dimple. From there the numbers go downward on the left side: 1, 2,3,4,5,6,7,8 and then you are at the bottom of the chip. cross over to the right side of the chip and the pin at the bottom is pin 9. From there the numbers go up as the position goes up on the right side: 9,10,11,12,13,14,15,16 -- 16 is at the top right across from the dimple.


Image
Another shot. In this one you can see pretty well where the wires go on the MJLJ board. The BT module is out of focus, but the Red wire connects to VCC. The Brown wire connects to GND. The Yellow wire connects to TXD. The Orange wire connects to RXD.


Image
An over-all shot. Not much for details but it gives you an idea how things go together.


OK, I have reassembled the MJLJ unit with the BT module "sandwiched" in between the rev limiter and the main MJLJ board. Taking it out to the car for final testing now.
...Bob

brentp
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Post by brentp »

Looks good.

A couple of tips:

* anchor the soldered wires to the board with some hot glue to form a form of strain relief.
* if you make a plastic end plate, you can possibly put the BT module inside of the enclosure so the RF can escape.
Brent Picasso
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bobclevenger
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Post by bobclevenger »

Checked out the installation. It works with both my Panasonic laptop and with my Lenovo tablet. Good communication anywhere in the car and within about 10 feet around the outside of it. Plenty of range for the purpose. I haven't tried to upload a map yet, but I do not expect any problem with that. The MJLJ module lives in the glovebox and now I don't need to have a cable dangling from it. :D Glue on the soldered wires on the PC board is a great idea! BT range is quite adequate with the aluminium end caps and the BT module inside of the case.
...Bob

bobclevenger
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Post by bobclevenger »

Update:

I have the same failure to "write ignition information" and "commit configuration to flash" that Tightwad had.

I also tried using PC Jolt and it works to do those things. It also has the benefit for tablet users of enlarging the advance curve matrix (for want of a better term) along with the size of the overall program window. That's very good. That matrix of bins gets very hard to read when you are using an 8" screen. It's particularly frustrating when you rotate the tablet to landscape mode and maximize the window and the advance bin matrix stays the same size (using less than half of the available screen area)! The advance figures in the bins are a bit small for my old eyes. It does not have datalogging capabilities and the virtual gauges can't be configured by the user. Those are negatives. When I start it up it complains about something being missing, but continues from there. I don't know if that's a problem or not. PC Jolt also does not have the "tuning" mode. PC Jolt is still in Beta, I know, but it and the Autosportlabs program are what is available.

All-in-all I prefer the Autosportlabs configurator and I'd use it exclusively if it would allow uploading of maps to the program and to the flash memory in the car via a working BT link and if it would resize the bin matrix to fit the size of the overall program. Any chance of that happening in my lifetime?
...Bob

brentp
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Post by brentp »

As we are working on the new app supporting Megajolt 2 we'll work in compatibility with the existing Megajolt/E. There will be an opportunity to add enhancements at that point.
Brent Picasso
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bobclevenger
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Post by bobclevenger »

That's good to hear. Now all I have to do is stay alive and wait. :)
...Bob

bobclevenger
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Post by bobclevenger »

While I'm waiting for the MJ2 update (Hey, any idea on when one could be able to buy the MJ2 and how much it would cost?) I shot a few more photos.

Image
This shows the dollop of hot glue I applied to the wires that are soldered to the MAX232A chip as a strain relief. Thanks for the idea, Brent!


Image
This shows the HC-06 Bluetooth module nestled between the main MJLJ board and the Hard Rev Limiter board as they are about to slide into the aluminium case.


Image
This shows the PC Jolt program display in full-screen mode on my tablet's 8" screen. As you can see, the ignition data are displaying just fine.


Image
And here is the MJLJ Configurator ver. 4.0.2 in full-screen mode on the same tablet also showing ignition data just fine.
...Bob

brentp
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Post by brentp »

super!

We're spinning new hardware for it soon. Price will be compelling.
Brent Picasso
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bobclevenger
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Post by bobclevenger »

I may feel compelled. :)

Just what advantages will it have over MJLJ/E?
...Bob

bobclevenger
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Post by bobclevenger »

One more thing --- will it connect to the EDIS module the same way, with the same connector?
...Bob

brentp
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Post by brentp »

Bob, do you have the end plates on the unit as before, with the BT module mounted inside? In other words, the only RF opening is through the molex connector?

MJ2 is designed to operate without an EDIS module; it's fully independent.
Brent Picasso
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bobclevenger
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Post by bobclevenger »

Yes, the aluminium endplates are both installed. Plenty of RF gets out unless you need to monitor your engine from a distance. It works anywhere inside the car and for about a 10' radius around it.

Going to have to give that MJ2 a look when it shows up (need a beta tester?). If it doesn't require TOO much reworking of my engine (trigger wheel and sensor probably won't get changed -- that's too much work and expense).

Will MJ2 be a wasted spark system on an 8 cylinder engine? Or will it be COP (or C near P)? Or will it do both? I believe I read it will be wasted spark, but things may have changed.

You have got me far too interested in this. :)
...Bob

brentp
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Post by brentp »

We're planning a couple of variations - one has 8 coil drivers for wasted spark up to 16 cylinders (who would do that??) or full sequential for 8, using modern coil-on-plug modules.

The other version will have coil drivers on board for simpler applications using standard coil packs.

We'll be looking for beta testers, for certain!
Brent Picasso
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