GPIO - what do users want?

racingmini_mtl · Post by **racingmini_mtl** » Thu Jan 03, 2008 4:27 pm

After getting some feedback from Bruce and from the comments here, I'll design a basic board with MS2 as the basis. Before I present the results, I'll again contact Bruce to make sure everything is acceptable to him and that it's not seen as too much of a competitor to the GPIO board.

I'll then show it here and I'll see if there is enough interest to get some boards made.

Jean

Post by **jsmcortina** » Thu Jan 03, 2008 4:36 pm

racingmini_mtl wrote:I'll then show it here and I'll see if there is enough interest to get some boards made.
Jean

Good work!

James

hassmaschine · Post by **hassmaschine** » Thu Jan 03, 2008 4:58 pm

jsmcortina wrote:If the quick board was half circuit and half proto area that would be even more DIY-able. Anyone who didn't want the proto section could cut it off anyway.

Don't be afraid of SMD either - aside from ICs with lots of pins, the other devices can be hand soldered without to much bother. i.e. use the VND5N07 and SMD base resistors. You can pack more onto a small board than using TO220 packages.

I like this idea - also, I agree that soldering SMD parts is not that difficult if you have soldering experience. if you built your own MS board and stim, you've probably learned how to solder pretty well by now.

racingmini_mtl · Post by **racingmini_mtl** » Fri Jan 04, 2008 6:57 pm

I have had more contact with Bruce and he's not enthusiastic about having a CAN board with generic I/Os. It is understandable because that's basically what the GPIO is. I had thought that the fact that this would have been a much more basic and DIY board with an MS2 would have made it ok but apparently not, which is fine.

As he mentioned, there is nothing on this board that is not available on the GPIO (even the high side driver can be done by replacing an NPN by a PNP in a low-side driver and drive it by another low-side driver). And with the GPIO only weeks away (according to him), I can see why he doesn't want a board competing directly with it.

So based on this, I'll stop working on an I/O extender board, at least for now.

Jean

devojet · Post by **devojet** » Fri Jan 04, 2008 7:17 pm

Sounds like bruce brought up some good points there. I didn't think of obtaining high side drivers like that, maybe the GPIO will suit my needs. I guess if you want something basic just stick an MS2 card onto a bit of vero board otherwise just buy a GPIO or a second megasquirt to handle your extra IO needs.

I think I will stick with MS2 and Vero board for now to run james's transmission code and see what happens when GPIO is released.

Cheers

Daniel.

racingmini_mtl · Post by **racingmini_mtl** » Fri Jan 04, 2008 7:30 pm

The funny thing is that before getting Bruce's message about the high side driver, I had decided to make the high side driver configurable as either a high side driver or as a low-current low-side driver and a high current low-side driver. This could be done by switching some components and using a couple of jumpers.

Jean

JET · Post by **JET** » Sat Jan 05, 2008 3:11 pm

Where is one supposed to put all of these full sized boards like the GPIO if all you need is a few added inputs/outputs on a MS2 to get the same basic functionallity as MS1-extra in the same case?Honestly for the general stupid MS user like myself you can't keep track of what all these boards(Gpio,router,sequencer,yadda, yadda etc.) are supposed to do or how you are going to integrate them in the minimal space that most people have to work with.Maybe if these boards were modular in hardware nature where you could stack them connected to the main board I can see the value.So I take it we are just supposed to keep staking cases untill the next version of MS comes out for a little extra functionality?

6040solder · Post by **6040solder** » Sat Jan 05, 2008 3:52 pm

apparently the gpio board is supposed to fit in the same case with some enginuity and work in harmony with the ms2. the trouble i see with the gpio is how specific it is in its io layout. to be properly gp it would need 16 of each type of circuit for 16 outputs, but its got something like 3 of each or the equivalent. ms2 + veroboard is the way to go for maximum flexibility and economy it seems. a little home made board to run a ms2 card on for that purpose wouldn't be too hard to come up with in any case, just not as tidy as Jeans proposed solution.

Brad-Man · Post by **Brad-Man** » Sat Jan 05, 2008 4:23 pm

Speaking as someone who will be buying a GPIO to control a 4L60E automatic, along with an MS2, I wouldn't mind having a smaller board with a limited # of IO's available for a turbo'd car running MS2_Extra. Virtually, or near enuf to be virtually all of the circuits on the GPIO are going to be used by it to control the tranny....

devojet · Post by **devojet** » Sat Jan 05, 2008 4:54 pm

You don't need much to make a MS2 card work on some vero board. just need to pick up 5V, GND, 12V (for IAC chip), CANL and CANH from your V3 PCB. Then for the serial coms the MAX232 driver chip on the V3 PCB has two spare RS232 drivers, but you will have to make a custom DB9 adaptor cable to use them. you just need to connect TX and RX from the MS2 Card to CTS and RTS pads on the V3 PCB.

Once those basics are done you can just connect what ever external circuits you would like. This is what I had planned for my own trans controller.

Brad-Man, Have you seen James's transmission code? he wrote it for Microsquirt but you could use it on GPIO and it doesn't use all the IO. You can find it on the Microsqirt web site.

Cheers

Daniel

Keithg · Post by **Keithg** » Sat Jan 05, 2008 7:09 pm

Like the topic says... What I want is more I/O for an MS2. What I don't want is to spend a grand to get it. MS is about DIY and learning. As we all know, the MS1 has more flexibility and more I/O potential, but is limited in its precision and programming arena (lack of variables and general space). What I would like to see is a simple way to get the precision and power of a MS2 but with more I/O. As it is, MS2/E is limited to 4 spark outputs. So 4 cyl COP or 8 cyl W/S. What about a 5 cyl? What about 6 cyl COP? The one thing I really wanted to see in MS2 was a true PWM output. It does not exist. With CAN to a spare MS2, it may be possible. With CAN to a non-stepper-encumbered-processor, it looks even more possible. It would be nice to have a DIY avenue parallel to Sequencer. I do not perceive Microsquirt or GPIO to be as DIY as MS1, for example. Maybe that is my problem, though.

$0.02

KeithG

Brad-Man · Post by **Brad-Man** » Sat Jan 05, 2008 9:56 pm

Daniel:

Yes, I am aware of the Microsquirt solution, but want the GPIO based for communication w/MS2.

I try to see everything that James and Jean do - I'm trying to learn!

I am building p&h boards from Jean and got one of the first JimStim boards..

KGB · Post by **KGB** » Sun Jan 06, 2008 12:10 am

As a fun exercise, I printed out the GPIO circuits and try to cram these features in, on board to make it an MS2/Extra base board (ie, no code change) that runs in parallel to a stock ECU (hence no idle and FP needed)
1) 4 logic-level spark, 4 high-impedance Injector (only 2 injectors are supported in the current code, but there is room for 4 using VND5N07FI which is ISOWATT220 form)
2) Table Switch (prefer Active High although it's laid out better for Active Low)
3) Launch Control Switch (can do both Active High/Low, but if made Active Low then I can jumper around to swap circuits with 2)
4) Boost Control
5) Crank + Cam VR
6) Baro
7) Water Injection (even though the code is not there in MS2/Extra, there is room on GPIO, I assigned E4 for the Pump relay and T6 for Valve)

2nd O2 is possible, but Knock Sensing require external circuit

Ended up with 1 spare VR in (on pin T7), and one stage Nitrous is possible by using Water Injection circuits, or take 2 injector circuits.

I really need to see the final board to see if my components would work the way I wanted, but in the ideal case, you can cram another GPIO board in the existing case with jumpers in between for CANbus. With code change it might be possible to enable some more features (Port B4 and E4 are currently marked for IAC Enable and FP, neither of which I need). I would probably have to ditch the AMPSEAL and use something else if I really wanted to cram 2 GPIO board as a MS2/Extra + GPIO combo in one case.

The other way is to use 2 GPIO board, but use some sort of ribbon cable on the big 50 pin jumper block to map the CPU pins to different circuits. With one board there are only so many components you can put on the heat sink, but with 2 you're pretty much have everything would need baring code support. I would say all the inputs relating to injection and ignition must be on a single chip, running a variant code that support using all those CPU pins. Again, there are only 8 hardware timers and 6 HW PWM that share pins with the timer (one of them can be freed up by changing the boot loader code to not use Port P5)

Post by **jsmcortina** » Sun Jan 06, 2008 3:53 am

MS2 on vero board shouldn't be too hard. Once you've flashed the code and done the inital CANid setup you don't need the serial, so it would be 0v, +5v, +12v, CANH, CANL.
Who's first to post a photo?

JET,
I agree that the Megasquirt portfolio can seem baffling at times. I am hoping that once the GPIO and MS2Sequencer are released products that things will be clearer. While they are still in development and then we in this topic are talking about different DIY addon versions here as well it must be mind-blowing for all but the most hardcore.

James

devojet · Post by **devojet** » Sun Jan 06, 2008 3:19 pm

I have posted a photo of my Trans controller in the following thread .

http://www.msextra.com/viewtopic.php?p=177183#177183

What do I WIN???

Post by **jsmcortina** » Sun Jan 06, 2008 3:23 pm

devojet wrote:I have posted a photo of my Trans controller in the following thread .

http://www.msextra.com/viewtopic.php?p=177183#177183

What do I WIN??? :lol: :lol: :lol:

You've won some firmware to experiment with!

James