any reason the DLP-TXRX gizmo wouldn't work on a GPIO?

[tmoble]

as mentioned in title, DIYautotune is selling the DLP-TXRX serial to USB converter for use with various MS EFI controllers. Any reason this wouldn't work with a GPIO? looks pretty simple, have to find a good place to cut the Rx/Tx traces on the board.


see http://www.diyautotune.com/catalog/dlpt ... p-141.html

[Bernard Fife]

tmoble,

The MS-II/V3 and GPIO serial circuits are electronically the same, so if it works with MS-II it ought to work with the GPIO.

However, the GPIO components are all SMD, so it is physically more similar to the microsquirt or 357 SMT board.

There are two via holes on the PCB for the TxD and RxD traces (located adjacent the corresponding CPU pins 39 and 38). Verify you have the correct ones by checking for continuity from the vias to CPU pins 38/39 and serial chip pins 11 (Tx) and 12 (Rx). These vias could be used to jumper to (they are *very* small however).

The traces you will need to cut are most easily accessible on the bottom side of the board, you can identify the using the vias.

Let us know how it goes.

Lance.

[tmoble]

after a couple hours tedious screwing around I finally got 2 wires inserted in the tiny vias near CPU pins 38 and 39. I found some 26 gauge stranded wire in my old wire box. turns out if I cut off all but two of the strands and struggle awhile I can get them to go thru the via. here's a couple pics but not soldered yet. not at all sure my current soldering iron is fine enough to do this without bridging or making some similar mess. Guess I'll find out. Do one from the top and the other from the bottom?

[edit] Pulled the pics, need to re-group on the close up digi-pics. Too bad about my 35mm stuff, I had a nice 50mm macro with extension, life size negs no problem. digi cams that get close to this are expensive.

Here's another try on the pics

tinyviabottom.JPG (38.56 KiB) Viewed 5913 times

tinyvias.JPG (36.81 KiB) Viewed 5913 times

[tmoble]

I did manage to get the 2 strand wire soldered into the tiny vias near the processor. When you say "MS-II/V3 and GPIO serial circuits are electronically the same" how much the same are they? In the instructions for the USB converter device they mention pulling the RS232 IC if it's socketed. Mine is not socketed, could I disable the the IC by cutting the power leg? I think it's PIN1 where the dot is. I see traces leading away from some of the other pins.

BTW, I'm doing this stuff on the board I fried, not the new one I just bought.