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Topic: Interfacing to a VFD29-2002I with Logic Controls board (Read 460 times) previous topic - next topic

Riccarr

Hello,

I salvaged a 20x2 VFD (VFD29-2002I) from a cash register machine; this was used for the $amount display on a pole beside the cash registered. The VFD itself is mounted to a Logic Controls circuit board, model LD9-PD3-7), part of the LD9000 series I believe.

Here is a LD9000 user manual PDF for the Logic Controls pole unit, using the VFD: http://www.bematechus.com/web/Documents/LD9_UM.pdf

There is a cable that has a DB9F  connector at one end (to plug to computer) and the other is an 8-wire either-net type (phone jack) type plug that connects to the circuit board.

Page 11 of the LD9000 user manual indicates the pin layout of the DB9 connector (8 wire version):

1. DCD (tied to pins 4&6 )
2 TXD to PC
3 RXD from PC
3. DTR (tied to pins 1&6 )
4. Ground
5. DSR (tied to pins 1&4 )
6. RTS (tied to pin 8 )
7. CTS (tied to pin 7 )
8. NC

Questions ...

- Can the arduino UNO talk RS232 directly to this device (with libraries) or do I need to use ardware for RS232 conversion to TTL ?

- what does it mean (tied to pins 4&6) ?  Does this mean a wire jumpers pin 1 to both 4 & 6?

If anyone has general comments on strategy to use this VFD with my arduino I'd appreciate your feedback.

Thanks.

raschemmel

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Can the arduino UNO talk RS232 directly to this device (with libraries) or do I need to use ardware for RS232 conversion to TTL ?

NO. The arduino is TTL (Transistor-transistor Logic , which means 0 to 5 Vdc to you). You need a level converter like this one:
http://www.ebay.com/itm/RS232-To-TTL-Converter-Module-COM-Serial-Board-MAX3232-With-Dupont-Cable-/221372796843?pt=US_Parallel_Serial_PS_2_Cables_Adapters&hash=item338ad8cfab

Quote
what does it mean (tied to pins 4&6) ?  Does this mean a wire jumpers pin 1 to both 4 & 6?

YES

Quote
If anyone has general comments on strategy to use this VFD with my arduino I'd appreciate your feedback.

You don't need comments or strategy, you just need to understand what the datasheet says. Everything you need to know should be there. What you need to do is pour yourself a tall cup of coffee and sit down and read the manual. I would start on page 2. Read that and come back and tell me what you learned about the display you have. Or if you don't want to start there, you can draw a schematic (or wiring list) of the db9 cable you are going to make. Take a close look at the photo of the converter you need and tell me what kind of connector you are going to put on your cable . FYI the converter only has Rx & Tx pins on the TTL (ARDUINO) side. Attached is an image of the connector you need to plug into the converter  you need.
Arduino UNOs, Pro-Minis, ATMega328, ATtiny85, LCDs, MCP4162, keypads,
DS18B20s,74c922,nRF24L01, RS232, SD card, RC fixed wing, quadcopter

Riccarr

Hi raschemmel ... thanks for that reply.

I don't actually need (want) to stay with the DB9 connector since its just the arduino and the VFD display involved or my project, so I would prefer to just cut it off and then have the loose wires at one end and the Ethernet connector at the other that plugs into the circuit board.

Your link to the convert is good, thanks. I guess I could still use this; the cable I have is a DB9 female and that converter is also female. I'll look to see if a male version exists or else I could wire plug to plug.  On the other hand, now that this has pointed me to the MAX3232 chip, I could just get that and there seems to be plenty examples on using the chip alone in RS232 arduino circuit.

On the otherhand, a local used gadget shop has the same used VFD with Hitachi driver already on it, for $25, so I may jump wimp out and buy that. I spent long enough time on this project already, and I already have a LCD screen working with it. I just wanted a VFD instead because its for in my car and feel it would view better than the LCD would.

Thanks for the confirmation on the converter and direction. I'll consider my options here and see which way I want to go.

Cheers!

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