Various comments

[Wouter de Waal]

Hi again

By now everybody must know that I am +- the latest member of this list.

I grabbed the archive file from the majordomo and looked it through. Seems
as if everybody gives a description of who / what they are, so here goes:

I graduated about two years ago with a Masters in Electronical Engineering,
subjects Digital Signal Processing, Computers & Telecommunications. While
at university I built a 68000 computer. Specs as follows:
3 x Eurocards on proprietary DIN41612 A/C bus
Card 1: 68000, Interrupt logic, clock, buffers
Card 2: 64K Ram, 192K Rom, Rom vectors to $000000 for reset, then Ram gets
        mapped there to enable interrupt vector changing.
Card 3: 2 x UARTS, Parallel port, Timer.

All cards are _single_ sided, with parallel jumpers on component side.
(No Thru-hole plating was available at my budget, namely 0)

Development cycle consisted of:
1. Write code (assembler)
2. Hand assemble to hex
3. Type hex into debug on PC
4. Blow Eproms
5. Go home, stick Eproms in and single step till first error
   (Oh yes, single stepping is just a flip-flop controlling /DTACK,
   set by /AS and reset by a pushbutton)
6. Goto 1

Using this I got a pretty nice monitor kernel working.

(Please all stand in line and shout "Masochist")

At the start of this year I got Internet access. Great. Since then I've
got the Dr. Dobbs tiny basic working, after getting quite a good assembler
from bode.

The latest is that I've actually got the Gnu compiler to run under LynxOS,
which happens to be a real time Unix. Pretty expensive for a hobbyist though,
but we're the local resellers. Quite a good Unix. But I'll hopefully
be getting Linux in a couple of weeks time. So John, please let me know
what to do to get gcc running and emitting 68000 code that I can use
for a simple embedded system. And what do I use for libraries?

Anyway, getting back to EFI.

I've just rebuilt a VW Type IV engine, which will be going into my Puma
soon. (A Puma is a glassfibre body sitting on a bug chassis, that was
produced locally and in Brazil. Probably still is being produced in Brazil)

This engine uses D-Jetronic, and being a tinkerer as well as the abovementioned
masochist, I would like to play with the system. For starters I'll look
at the inputs to the EFI box, and the outputs, and get the map. Later
I can start the specialised stuff, like using better sensors. Even
after reading the archives, I can't figure out what the consensus is on
hot-wire mass sensors versus manifold vacuum sensing. Vacuum seems to
be cheaper and easier from a hardware point of view, but Bosch sez that
it's less accurate. Help!


Some comments on stuff I got out of the archives, if anybody is interested
in some semi-fresh input: