[Gmecm] Any USB developers out there?

[Craig Moates]

I'll put together a BOM with part numbers, vendors, and pricing. I'd think it'll be pretty economical.

Best regards,
Craig Moates


----- Original Message ----- 
From: "Steve Ravet" <Steve.Ravet at arm.com>
To: <gmecm at diy-efi.org>
Sent: Wednesday, December 27, 2006 1:14 AM
Subject: RE: [Gmecm] Any USB developers out there?


Hey Craig, thanks for sharing.  I have a few questions:

Is the 9 pin to OBD2 cable something that is standard or one of your
cables?  I used a DB-15 on mine, but was planning on moving to a DB-25
to allow more of the PIC pins to be pinned out (ie misc analog and
digital I/O).  But if the DB9 is standard I may switch to it.

I guess you use solder paste to do 0402?  In your experience (or anyone
else), does solder paste really go bad within a month?

After looking at yours I realized there's no reason to have the 5V
regulator in there, might as well always have the VCC stuff powered from
USB.  Eliminates parts and makes the BOM that much cheaper.  I'm also
going to use your board layout to fit the Pactec enclosure.

I'm writing my firmware in C, since microchip assembly makes my head
hurt.  As far as the host interface, I had planned on implementing the
SAE J2534-1 API.  (Yes, this is an SAE spec that specifies a windows
API).  This is a standard API for vehicle reprogramming but the API is
generic enough to work for normal scan tool operations also.  The spec
requires support for all vehicle protocols but USBVPW will only do VPW.
That SAE spec is now on the USBVPW wiki page, take a look.

What do you think your BOM cost is, including the PCB?

Speaking of PCBs, I have a number of small (couple square inches or
less) projects I've been wanting to do but it seems like most PCB houses
get offended if you do arrayed PCBs.  Is there a PCB place that will do
a 4x6 PCB with many individual circuits on it and not want to give me
all kinds of per project charges?  Otherwise the cost for these one-offs
is prohibitive.

--steve

> -----Original Message-----
> From: gmecm-bounces at diy-efi.org 
> [mailto:gmecm-bounces at diy-efi.org] On Behalf Of Craig Moates
> Sent: Monday, December 25, 2006 3:01 PM
> To: gmecm at diy-efi.org
> Subject: Re: [Gmecm] Any USB developers out there?
> 
> Folks,
> 
> I updated the layout, and it's probably ready for a proto 
> run. Check it out if you like:
> www.moates.net/projects/
> Got tired of trying to squeeze those beefy 1206s in there so 
> went to mostly 0402. They're doable with magnifier and tweezers.
> 
> All the components are specified, laid out pretty well, and 
> labeled on the schematic and silkscreen.
> 
> I'll start working on the firmware shortly. Prefer C++ or 
> ASM? Guess I'll make it compatible with some of the 'other' 
> stuff out there.
> 
> Best regards,
> Craig Moates
> 
> 
_______________________________________________
Gmecm mailing list
Gmecm at diy-efi.org
Subscribe: http://lists.diy-efi.org/mailman/listinfo/gmecm
Main WWW page: http://www.diy-efi.org/gmecm