Unfortunately no one can be told what fun_plug is - you have to see it for yourself.
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Had to put this down for a couple of weeks, but back on it now, and hoping to get it up and running this weekend. I've been following the serial port walkthrough, but just have one question about the wiring from the Futurelec board to the 9-pin serial connector (I'm wiring this straight through and not using an intermediate RJxx connection):
So here's what I'm thinking:
DNS-323 Futurelec Serial
------- --------- ------
Gnd ___________ Gnd Vcc 1
Rx ___ Tx1 Rxd _____ 6
Tx ___\____ Rx1 Txd _____\_____ 2 2=Rx
Vcc __ \ \__ Tx0 Gnd __ \ 7
\ \_____ Rx0 \ \___ 3 3=Tx
\_______ Vcc \ 8
\ 4
\ 9
\____ 5 5=GndThe DNS-323 to Futurelec should be as per the serial guide. For the Futurelec to serial wiring, I'm assuming that I need the Tx/Rx crossover, and the ground is pretty obvious, but what to do with the Vcc? Is this even needed? Most of the RS232 specs I've seen (here's a typical one http://www.anotherurl.com/library/rs232.htm) don't actually have this on at all.
Cheers,
Barney
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Most likely you can just ignore it.
Vcc is used to provide power and is not a part of the RS232 standard, which is why you're not finding it in the spec - although I notice you say "most of the RS232 specs you've seen don't actually have it", can you provide to link to one that does - I've never seen one with it.
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Sorry, my fault: no, I've never seen an RS232 spec using Vcc. I've looked at a lot of diagrams over the past couple of days, and seen ADM3232 circuits using the 5v Vcc. So I guess the question I was asking, was "do I need to power the ADM3232 vith 5v, and if so where do I get that from?"
A bit more searching turned up this description, which answers the question:
The ADM3232E transceiver is a high speed, 2-channel RS-232/V.28 interface device that operates from a single 3.3 V power supply.
...
Four external 0.1 μF charge pump capacitors are used for the voltage doubler/inverter, permitting operation from a single 3.3 V supply.
So the 3.3v from the DNS-323 end is sufficient to power the chip, and the Vcc is not needed. I just wanted to fully understand what was going on before I put it all together.
Cheers,
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