Just a note on PA0, boost control, and output conflicts
#1
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Just a note on PA0, boost control, and output conflicts
So today I changed a couple inputs/outputs on Aaronc7's DIYPNP so he could use launch control and EBC and I ran into the same wiring issue that I had when I built my MS.
Problem is somewhat discussed here: https://www.miataturbo.net/megasquirt-18/diypnp-cant-get-wled-output-turn-radiator-fan-51862/
Basically, if you follow the DIYPNP documentation, it has you use PA0 for your radiator fan output. This is fine and dandy unless you happen to want sequential injection and EBC. In this scenario, two of your PWM outputs are used up by the sequential module -- PT6 and PT7. And if you followed the documentation, your other two are being used for 1. IAC (this is fine) and 2. radiator fan (not cool). So now you've got none left.
The reason I am putting this up is because on Aaronc7's MS, EBC was wired into PT6, and when it's done like this , you get that nifty little 'additional injector conflict' message if you select PT6 as the output. And the really neat part is that even if you then turn off EBC, if that output is still selected, you'll still have a config error. The only output that could be selected was Fidle and that would cause an error, too, unless EBC is disabled. I don't know why the behavior is inconsistent, this is just what I found.
So...because the is the second time I've run into this problem and I didn't build Aaronc7's MS (not trying to call you out "Jared from Subway" double, you are probably on autopilot when you build these now and your wiring is very neat and pretty), I thought I'd mention it. So, here's how I would wire it for no conflict:
FLEX - Launch Control
WLED or ALED - Radiator fan (BIG NOTE: These outputs will drive the relay directly. Wiring them to an onboard relay will cause the output to not work). ALED was used for VICS on Aaronc7's MS.
PA0 - Boost Control
PT6 and PT7 - Sequential (you have no choice)
I know most of you haven't had an issue, so feel free to tell me to STFU, but I thought it was worth mentioning.
Problem is somewhat discussed here: https://www.miataturbo.net/megasquirt-18/diypnp-cant-get-wled-output-turn-radiator-fan-51862/
Basically, if you follow the DIYPNP documentation, it has you use PA0 for your radiator fan output. This is fine and dandy unless you happen to want sequential injection and EBC. In this scenario, two of your PWM outputs are used up by the sequential module -- PT6 and PT7. And if you followed the documentation, your other two are being used for 1. IAC (this is fine) and 2. radiator fan (not cool). So now you've got none left.
The reason I am putting this up is because on Aaronc7's MS, EBC was wired into PT6, and when it's done like this , you get that nifty little 'additional injector conflict' message if you select PT6 as the output. And the really neat part is that even if you then turn off EBC, if that output is still selected, you'll still have a config error. The only output that could be selected was Fidle and that would cause an error, too, unless EBC is disabled. I don't know why the behavior is inconsistent, this is just what I found.
So...because the is the second time I've run into this problem and I didn't build Aaronc7's MS (not trying to call you out "Jared from Subway" double, you are probably on autopilot when you build these now and your wiring is very neat and pretty), I thought I'd mention it. So, here's how I would wire it for no conflict:
FLEX - Launch Control
WLED or ALED - Radiator fan (BIG NOTE: These outputs will drive the relay directly. Wiring them to an onboard relay will cause the output to not work). ALED was used for VICS on Aaronc7's MS.
PA0 - Boost Control
PT6 and PT7 - Sequential (you have no choice)
I know most of you haven't had an issue, so feel free to tell me to STFU, but I thought it was worth mentioning.
#3
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no offense taken. yes im on autopilot. and what you say makes complete sense and something that didn't dawn on me whenever adding seq. injection since I try to build all my units alike.
I take more offense to the jared comment
I take more offense to the jared comment
#4
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For reference, here's a link showing a usage chart for all available extra DIYPNP I/O:
http://www.diyautotune.com/diypnp/do...a_outputs.html
As you can see, there are often several pins that can perform the same function, but some functions can only be handled by certain pins.
http://www.diyautotune.com/diypnp/do...a_outputs.html
As you can see, there are often several pins that can perform the same function, but some functions can only be handled by certain pins.
#5
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hmm. I just made a similar table for myself. it lists all the functions and what outputs or inputs you can use for them. I also made a pinout spreadsheet for the MS V3.0 and xpander that you can map it to. Maybe I'll clean them up for public consumption and share them on google docs.
#6
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I know I miswired mine because, like every other problem I've had with MS, I failed at reading. I'm sure that fewer people will make the same mistake since everyone is ponying up for sequential these days or using MS3.
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