Clarification of I/Os in MS2 and Sequential Shift Lights
#1
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I can't figure out how many I/Os I have remaining after all my mods. Basically, I'm building it exactly like Frank's MS2 build on his website with the Jbperf sequential board.
90-97 MS2 sequential | Frank's Westfield MX5 90-97 MS2 sequential |
In addition to the usual ones and these:
Spark A & B (D14 to IAC2B), (D16 to IGN)
Fan D15
Table switching R1
Launch control JS7
EBC IGBTout
1) Will I have enough outputs for 3 staged sequential shift lights?
2) If so, will these outputs work (JS2, JS3, JS8)?
3) Do I still skip the logic stage and only build the transistor stage, for the lights?
90-97 MS2 sequential | Frank's Westfield MX5 90-97 MS2 sequential |
In addition to the usual ones and these:
Spark A & B (D14 to IAC2B), (D16 to IGN)
Fan D15
Table switching R1
Launch control JS7
EBC IGBTout
1) Will I have enough outputs for 3 staged sequential shift lights?
2) If so, will these outputs work (JS2, JS3, JS8)?
3) Do I still skip the logic stage and only build the transistor stage, for the lights?
![](https://www.miataturbo.net/attachments/megasquirt-18/102004-clarification-i-os-ms2-sequential-shift-lights-shift-light-seq.jpg?dateline=1391495286)
#3
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See the pin usage chart in the MS2 manual:
MS2-Extra Hardware Manual
You can assign any of the pins labeled "programmable output" so long as they are currently unused.
MS2-Extra Hardware Manual
You can assign any of the pins labeled "programmable output" so long as they are currently unused.
#4
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You can if you give up Boost OR the fan output.
I take it you don't want to give up on boost, so your only solution is to install a 1.6 thermosensor and use D14 for your shift light instead of for the fan.
JS0 is your crank input
JS2 is unused and can be used for your shift light (= PT7/IAC2)
JS1 and JS3 can not be used because JS0 and JS2 are in use (you can only use one set OR the other set, not both sets at the same time)
JS4 and JS5 can only be used as an input or tacho output, not as programmable output
JS6 and JS8 can only be used as a CANbus, not as a programmable output
JS7 (PE0) is your launch control input (but can not be used as programmable output anyway)
R1 (PE1) is your table switch input (but can not be used as a programmable output anyway)
JS9 is used to activate JS0 and JS2
JS10 is your cam input
JS11 is your boost output (BUT could be used as a programmable output if you delete boost)
D14 is spk A
D15 is your fan output (BUT could be used as a programmable output if you use a 1.6 thermosensor)
D16 is spk B
Fidle is your idle output
I take it you don't want to give up on boost, so your only solution is to install a 1.6 thermosensor and use D14 for your shift light instead of for the fan.
JS0 is your crank input
JS2 is unused and can be used for your shift light (= PT7/IAC2)
JS1 and JS3 can not be used because JS0 and JS2 are in use (you can only use one set OR the other set, not both sets at the same time)
JS4 and JS5 can only be used as an input or tacho output, not as programmable output
JS6 and JS8 can only be used as a CANbus, not as a programmable output
JS7 (PE0) is your launch control input (but can not be used as programmable output anyway)
R1 (PE1) is your table switch input (but can not be used as a programmable output anyway)
JS9 is used to activate JS0 and JS2
JS10 is your cam input
JS11 is your boost output (BUT could be used as a programmable output if you delete boost)
D14 is spk A
D15 is your fan output (BUT could be used as a programmable output if you use a 1.6 thermosensor)
D16 is spk B
Fidle is your idle output
#5
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Frank to the rescue! Thanks, that really clarifies things. I've decided to build a shift light circuit outside of MS2 to save a programmable output - considering water injection for JS2 instead.
Is MS2 EBC w/ current code worth doing? I don't hear much about it other than early early reviews of it being difficult to tune.
Thanks again.
Is MS2 EBC w/ current code worth doing? I don't hear much about it other than early early reviews of it being difficult to tune.
Thanks again.
#6
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FWIW, that circuit is missing a diode between the 1st and 2nd stage.
Without it, the 2 stages are on at the same time.
See here for the correct circuit
Without it, the 2 stages are on at the same time.
See here for the correct circuit
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