VB921 confusion

DrSeuss · Post by **DrSeuss** » Wed Aug 02, 2006 9:26 am

Hi,

I've tried reading all the info and searching for vb921 installation information.

i've got a v3 mainboard and wish to run 2 coils in wasted spark format. This requires 2 vb921 chips. What i'm interested in, is solely how to install them on the board. I've gone over the information available, including a search.

What jumpers do i need to install, which additional wires am i required to run. Is there a good earth point to utilise? I guess i have to run the wire directly into the unused pin on the db37 (for the second vb921).

DrSeuss · Post by **DrSeuss** » Wed Aug 02, 2006 9:27 am

I am sorry to have to ask these questions. But I simply can't make head nor tail of the information available to me.

TT350chevelle · Post by **TT350chevelle** » Wed Aug 02, 2006 10:25 pm

Hi Doc... did you read this?
http://megasquirt.sourceforge.net/extra ... wheel.html

DrSeuss · Post by **DrSeuss** » Thu Aug 03, 2006 3:55 am

Hi, i'm beginning to make sense of it all.

Is the ground plane on the proto area sufficient for the vb921?

The bit which confuses me is the pull up resistor used on the diagrams halfway down the page. Its just not quite clear enough in my own head yet. Could anyone post pictures of their built megasquirt?

Cheers

Sam

p.s. sorry for seeming so dim.

masterx81 · Post by **masterx81** » Thu Aug 03, 2006 4:16 am

In my install i've bolted the other vb on the top of the 'original' one, with a spacer and a alu heatsink, they shares the same screw.
Seem more than sufficient...

Post by **jsmcortina** » Thu Aug 03, 2006 5:48 am

I replaced R43 with a jumper and used that as the ground for the second VB921.

James