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mcsvt
10-12-2006, 02:34 PM
Looks like I will have a flashable smec soon and now I can't find the info for the serial interface and cable.

Does anybody have links? Derek posted a part number for the diag. port connector and d-cal has a schematic for what leads do what... But I am trying to find a write up.

If anybody can help or wants to make if for met, let me know :D

Thanks,

Frank
10-12-2006, 03:11 PM
You will need to have a TTL to RS232 voltage level convertor. This is because the voltage level at the ECU is TTL aka 5volts. The RS232 serial port on the computer is over 12volts. There are several different methods of converting, however the best uses a MAX232 chip. That is the part number he probably listed?

mcsvt
10-12-2006, 03:16 PM
Ok, that is what I kind of thought. I just can't find the write ups on making the converter.

The connector part numbers are just for the diag port connector,
summit part number: 20130
OTC number: 212635

rhubbard
10-12-2006, 10:28 PM
Is this it?

http://www.schmartboard.com/index.asp?page=products_populated&id=84

rhubbard
10-12-2006, 10:29 PM
oh, could you post the wire diagram for attaching the serial converter to the smec?

mcsvt
10-13-2006, 09:37 AM
Sure, see attachment :)

That board you listed looks like it does what's needed, but I am not sure I see where the diagnostic port wires would be attached... I see the serial connection(obviously)...

rhubbard
10-13-2006, 10:12 AM
GND goes to the pad just below the crystal
+5V goes to the edge side of resistor R103 (right next to the pad)
RD (receive) goes to pin 12 of Z20 (CPU)
TD (transmit) goes to pin 11 of Z20 (CPU)


Does this help? I don't actually have the board so I can't give you the exacts.

Nevermind, I found this picture. Credit goes to Geoff Allan for pic and info.

http://i94.photobucket.com/albums/l119/rhubbard4140/untitled.jpg

mcsvt
10-13-2006, 10:23 AM
Ah right, not sure how I missed that. Thanks :) Looks like I can build my own now :thumb:

GLHNSLHT2
10-15-2006, 12:38 PM
that picture looks like the wiring from an LM caught fire on the couch? How does that help?

cordes
10-15-2006, 12:40 PM
that picture looks like the wiring from an LM caught fire on the couch? How does that help?

I think it was the directions given along with the pic that really helped.

mcsvt
10-15-2006, 06:01 PM
Yeah that shows where the wires enter the converter. Much help :)