> -----Original Message-----
>
> 5 REX !!! ? wow!
I ordered six boards and corresponding parts, plus two of the Macronix flash
chips to test, because I needed to build four of them and I thought I might
mess one or two of them up.
As it turns out, I did mess one module up (the third one I built) where the
CPLD now seems to be fried and I gave up on the whole module (I don't know if
the CPLD was bad to start with, or if bad soldering on the flash chip
contributed, but it did work for a few minutes while iMPACT was telling me
there were 17 CPLDs on the JTAG bus, then the whole thing quit and the 3.3v bus
is shorted to ground now...)
I spent this long weekend building the kids' REX modules - they did their own
castellation by hand, and soldered the ICs after I tacked them down, and loaded
the CPLD firmware and REX software. Now everybody has REX in our house and
everybody is Very Happy. :) My son can borrow my machine and his sister's
machine and uses them to write BASIC programs to play music in sync as
three-part harmony, without risk of clobbering our files accidentally.
I've got one more I could build when I have another free evening. Might build
it as a spare or to mail out to someone who needs one.
> I should have said - losing power and backup battery... which takes a
> while!
Yeah, I hadn't tested my own machine to see how long the poor little
34-year-old nicad battery would hold the RAM and RTC, beyond the few minutes it
usually takes for a battery swap. (Mostly because I didn't have REX and it
would have meant TBACK to recover after reaching the time limit, which is not
terribly painful but I didn't want to know *that* badly and I didn't want to
stress the old nicad needlessly. Maybe I'll test one of the kids' machines
before doing the supercap upgrade...)
jim
