I/O Board ...

[Sandy]

>Robert McGhie (your mail bounce, so here it is)

The driver boad has a generic approach, the injector are not really
specificly tied to an output, the I/O on the 68332 does impose some limits,
as it totals only 16 TPU I/O lines. So I would say that driving the extra
injectors with the approach of 2 I/O boards may not be the simplest, but
may work with some hacking on the 68332 size. It may not really be
necessary, as I think may be some other outputs that can be made available
on the 332'. These could be used to a couple of Driver Boards. Some
Buffering will be needed as the CPU can't drive the injector drivers
directly (or shouldnt) but if you don't mind the extra injectors not being
tied to the main 8, it may be much easier to just do them in a batch mode.
One the motor is past the low idle speeds, it has been argued that the
direct injecton doesn't buy that much, so you could really just make use of
a couple of extra output lines and  pulse a bank of the extra injectors
that way. Or, you could just get some 72lb/hr injectors and be done with it
;-). Check some of the injector size programs for the engine and hp
requirements, you will be surprised how much a 52lb injector can make at
80% duty cycle, even more by the 72lb/hr. The down side is that the big
injectors are expensive and the spray is not as 'atomized' as the smaller
units.

Sandy

At 06:34 PM 6/20/98 -0800, you wrote:
>I know that you are busy so I will make this short.
>1. Am I correct that the I/O board is limited to 8 injectors (2 
>driver boards) plus 4 ignition coils (1 additional driver board)?
>2. Can 2 I/O boards be used with a single CPU board so as to drive 16 
>injectors?
>Reason for question is to be able to switch or add additional 
>injectors on a turbocharged V8 engine
>
>Thanks
>Robert McGhie
>