Another comm issue...but a different one

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Big Thurs
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Another comm issue...but a different one

Post by Big Thurs »

So I don't get to drive my ms1 mr2 much. Its been a year or so since I last had the computer connected to it for tuning. When I tried to connect the other week, there was no communication. Since then, I have poked and prodded around the board (V3) and even replaced the max 232 chip. With the processor installed I get an echo back in the mini terminal, no echo without the chip. I get echo back when the processor is removed and the comm pins on the socket are jumped. I cannot program the processor with or without the boot jumper, it only returns the initial character; "" or "!!". It seems the processor has failed, but the car still runs fine, only serial communication has failed. Any thoughts?
91 MR2 Turbo on V3 MSNE-e HR11d
Matt Cramer
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Re: Another comm issue...but a different one

Post by Matt Cramer »

What happens if you run the Port Check program?
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Big Thurs
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Re: Another comm issue...but a different one

Post by Big Thurs »

Port check finds nothing but an open port. Loopback test of usb-serial converter and rs232 side of max232 passes. I get echos when ms is unplugged, but no echo when ms is hooked up to the car with ignition on, with or without cpu pins 12-13 shorted. max232 pin 12 and cpu pin 13 are +5v with ig-on. No continuity between cpu pin 20 (vcc) and 13.
91 MR2 Turbo on V3 MSNE-e HR11d
Matt Cramer
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Re: Another comm issue...but a different one

Post by Matt Cramer »

Big Thurs wrote:... but no echo when ms is hooked up to the car with ignition on, with or without cpu pins 12-13 shorted.
Sounds like a problem with the MAX232.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Big Thurs
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Re: Another comm issue...but a different one

Post by Big Thurs »

That was my initial diagnosis, but replacing the max did not fix the problem. If I fiddle with the 12-13 jumper, I get serial jibberish returning in the terminal, so something is being read and converted to rs232 by the max232, right?
91 MR2 Turbo on V3 MSNE-e HR11d
slow_hemi6
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Re: Another comm issue...but a different one

Post by slow_hemi6 »

You can remove the ms1 processor and do a loop back at the main socket. http://www.msextra.com/doc/pdf/html/Meg ... .4-95.html
Find the Manuals up top under Quick links: Manuals. :RTFM:
Cheers Luke
Big Thurs
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Re: Another comm issue...but a different one

Post by Big Thurs »

I finally figured it out! It was a windows 10 issue, not a MS hardware issue. Basically I changed the latency timer in the usb-serial adapter advanced settings to 1msec from the default. I think it was like 15 0r 20msec.
ftdi settings.png
91 MR2 Turbo on V3 MSNE-e HR11d
Big Thurs
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Re: Another comm issue...but a different one

Post by Big Thurs »

So I tried it again, but no communication in TS3. I tried my old laptop on xp and it works just fine. Tried many different combinations of settings for the FTDI driver. I Installed megatune and it runs and communicates just fine. So the summary for future reference with a similar issue is that Tuner Studio 3 and Tuner Studio 2.9 will not communicate (including the terminal) and Megatune installs and runs fine and communicates normally for me in Windows 10. Back to tuning!
91 MR2 Turbo on V3 MSNE-e HR11d
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