First Success with Numerical Display (FOMOphobia) 2

This morning I woke up and looked at the calendar and started shitting bricks. A week and a half before the show. Ack. And still haven’t successfully talked to the Vorne 87/415 numerical displays. These things are beautiful if I could only get them to listen to me via the RS232 serial port.

I called up Scott at Vorne technical support who walked me through everything, wiring, switches, software, and serial commands.

Things are the things I learned from Scott.

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1. It is good if the RS232 serial cables are not reversed. Transmit to Receive and vice versa. Not Tx to Tx. Classic RS232 mix-up.

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2. The position of the dip switches matter, particularly switch 7 which has something to do with a pull-down resistor or some shit that involves a jumper which should be set to Sink. Naturally, you know more about this than I do, so you can talk endlessly about it in the comments below.

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3. Each numerical display has an address, and you need to use it to talk to the display. “Broadcast” doesn’t work.

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4. The Vorne software is useful for the test. I was running it on James’ vintage Windows XP machine, but talking to the serial port directly from my RPi should work too.

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5. Bonus discovery from Scott: There is a $#%@* software-addressable relay on board the Vorne with helpful screw terminals. I can make the relay click open or click closed with a simple command to the RS232 port. Rather than kill myself trying to get a relay (plus transistors and resistors and whatnots) to fire from the RPi’s GPIO pins, I can hook the alarm bell to the screw terminals and fire it with the command “<SOH>S0:R1<CR>” Goddamn magic, if you ask me.

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So with Scott’s help, I was able to talk to the displays for the first time. Very exciting.

And then…

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Just to make things sweeter, I got the displays working from the command line on the Rpi.

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Hell fucking yeah.

2 thoughts on “First Success with Numerical Display (FOMOphobia)

  1. Reply James Nov 26,2013 1:43 pm

    Awesome things happen after bricks are formed, proven once again here :-) I’m not going to mention pull up resistors, even once. Love that “ol’ stickers” has been so helpful and awesome find on the relay!

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