Build or Buy?

[ALIPPER at aol.com]

In a message dated 95-08-15 22:41:23 EDT, you write:

>I'm in the early stages of my EFI project and am trying to decide
>whether to start completely from scratch with cct design and
>board layout OR buy a commercial microController card - probably
>using a 8051.
>Does anybody have any suggestions or warnings about trying to
>build from scratch.  Is it a waste of time?...

Danny,
    Having recently worked with both the build and buy alternatives, it
really depends on how many you intend to make.  If it's just a single unit -
or even a few - then it is far easier (and cheaper in the long run) to buy a
microcontroller unit and program it.  Your choice of the 8051 as the CPU is a
good one.  Blue Earth Research (507) 387-4001 makes a number of excellent and
reasonably priced units - they send out free catalogs.  I've used their
Micro-440e very successfully.

As far as making your own PC boards goes, if you don't have access to a
numerically controlled (NC) drilling machine, it's a lot of tedious work.
 Even if you do, the layoutitself will take a professional dozens of hours
with a good CAD package.  Then you have to do the etching itself...then, the
debugging and hope that the original board is still usable...  Anyway, you
get the idea.  Good luck.


Al Lipper
alipper at aol.com