Flashable LM or Super LM?

[Tbird232ci]

Not sure how you mean?

I think he means building a stand alone staging limiter, or making a daughter board for the staging limiter.

I'm watching this closely, it may or may not be a game changer for me.

[roachjuice]

I think he means building a stand alone staging limiter, or making a daughter board for the staging limiter.

I'm watching this closely, it may or may not be a game changer for me.

Exactly what I mean. A separate box or something with adjustable spark cut staging limiter. And adjustable I mean right on the box or whatever. No computer programming. Dunno if that's possible or not.

[ShelGame]

Exactly what I mean. A separate box or something with adjustable spark cut staging limiter. And adjustable I mean right on the box or whatever. No computer programming. Dunno if that's possible or not.

Sure, it's possible. But, that's not a direction I would go in...

[85boostbox]

Subscribed

[intercooled]

I love the super idea and would love one

[Force Fed Mopar]

It has a staging limiter, but it's not a spark-cut. I'm trying to add it to the current T-LM code. But, I think I'm going to have to take away some RAM storage from current values to do it. I need at least 3 bytes of RAM, and basically everything is being used.

I think Alky Inj is still in there, that may get axed to allow the spark-cut to work.

The daughterboard for sure would be flashable. It would basically work like a '89 SMEC with double the RAM; and flash the same way the '91 SBEC's do using the USB-SCI cable that I make with the bootstrap wire and MP Tune.

In that case, I'd go with the Super LM.

Would this also be possible with the '84-86 LM's? Might make tuning them way easier too.

[ShelGame]

In that case, I'd go with the Super LM.

Would this also be possible with the '84-86 LM's? Might make tuning them way easier too.

It would work with the '86-87 for sure. Maybe the '85's. I haven't seen one up close to know for sure. The big difference between the '87 and the '86 is the replacement of the 2nd EPROM with a timer chip. But, My board would ignore that position on the original board completely. I think I can do it by only picking up the processor pins, and the A2D converter pins. Those positions and pinouts didn't change from 86-87. So, for sure this would work for the GLHS and all other 'T2' LM's and '87 T1 LM's. Others may need some other components added to run the 4-wire AIS.

The issue I'm looking at right now is the decoding for the port expander. I was hoping to use the existing port expander, but it has 2 chips used to interface it to the 6803. I just have to map those out and make sure it will still work with the new processor.

[ajakeski]

Sounds great. I'm in for a super or two, maybe three...

[Tbird232ci]

The 86 LM's would indeed need some other components to run the 4-wire. I remember hoping I had one of the few oddball LM's that came in the log cars that had 4-wire AIS capabilities. Once I got my 87 LM's, and compared them, the difference was pretty obvious. Made me sad.

Would you need a 86 LM to mess around with for this? I may have a spare.

[ShelGame]

The 86 LM's would indeed need some other components to run the 4-wire. I remember hoping I had one of the few oddball LM's that came in the log cars that had 4-wire AIS capabilities. Once I got my 87 LM's, and compared them, the difference was pretty obvious. Made me sad.

Would you need a 86 LM to mess around with for this? I may have a spare.

I think I have 2. And, I have a bunch of the transistors used for the AIS drive. So, I should be able to 'update' those.

Just as a progress report - I'm down to figuring out how they did the watchdog timer on the LM's. Since the 6811 has an internal watchdog, I need to disable the external one used on the LM. Just need to finish mapping it out and I can start to layout the board, I think.

[chilort]

I don't know how many would sell either. I think I might go ahead and do 10, and see if I can sell those, then decide to make more or not.

I don't think the hardware is going to be tough to develop at all. But, the new source code might take some time. So, I would need at least 1 person willing to help develop the special hybrid source code the SuperLM would need; since I don't have an LM car at my disposal.

Rob Mercer has my car now. If he'd be willing to play along and you wanted to work with Rob then let me know. The last part I'm waiting on is a custom ground F4 cam from Cindy. If I can get my cam then .....

[Force Fed Mopar]

It would work with the '86-87 for sure. Maybe the '85's. I haven't seen one up close to know for sure.

That LM you socketed for me was marked '85 Omni Turbo on the back...

[iangoround]

I'd take one. I love new toys.

[ShelGame]

That LM you socketed for me was marked '85 Omni Turbo on the back...

I think it was just the cover, though. Or was that actually an '85 LM?

[boost geek]

BAKES .anysuggestions for me?

[Force Fed Mopar]

I think it was just the cover, though. Or was that actually an '85 LM?

Not sure. It came with the '87 Omni I bought (and am now selling lol).

[85boostbox]

You have a PM Rob :thumbup:

[ShelGame]

It looks like there's not an easy way to disable the hardware watchdog on the LM. So, I think the SuperLM will just have 2 watchdogs - the LM hardware watchdog, and the 6811's internal COP watchdog timer. That shouldn't be a problem (though, pretty redundant). I just need to add a small bit of code to the SuperLM assembly source (aka, T/SMEC) to set the watchdog output bit every loop.

[wowzer]

does the hardware watchdog allow you to set how long it waits between checks, i.e. a timer divisor of some sort?

[ShelGame]

does the hardware watchdog allow you to set how long it waits between checks, i.e. a timer divisor of some sort?

No. But, my assumption is the timeout is long enough that it won't be a problem. In the LM code, the WD is reset every 11msec loop. We have the same 11msec loop in the SMEC code, so I don't think there will be an issue.

Interestingly enough, I think the 11msec for the main loop time may in fact come from the WD timeout. In the 6811, one of the WD timer options is 10.98msec. In the SMEC code, it's set to 6x that value or 65.5msec.