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ggajoch / vf60-vfd-display

Fujitsu VF60 display docs & drivers
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Description of RS-232 connection missing #2

Open eranmes opened 3 years ago

eranmes commented 3 years ago

Hi, I have a similar VFD display model (KD02906-1504) which seems to have similar connections and should be similarly easy to drive.

Your document mentions a serial connection (RS-232) - can you please describes the pins you've connected and the line level voltage?

Many thanks! Eran

ggajoch commented 3 years ago

Hi!

The pinout of the display is described in this picture: https://github.com/ggajoch/vf60-vfd-display/blob/master/docs/back.jpg

You basically need only GND, RxD, Vcc to drive it. Please share a picture what kind of connectors you have on your display.

You can find out the RS232 pins by measuring voltage beteen any pin and GND - for RX232 TXD it will be -5V or less. RXD can be floating, but it will probably be next to it.

Voltage levels are typical for RS232, I beleve I've used it with MAX232 with -5 V and +5 V levels.

Good luck!

eranmes commented 3 years ago

Thank you for the details! Just to make sure I understand correctly: To power the display I need to feed it 12V. Given a usb-to-serial converter, I need to connect the GND, RxD and TxD pins from the serial port to the display.

Do I also need to connect the VCC pin? Or would the VCC pin from the serial port be connected instead of the 12V power supply to the display?

Connectors

ggajoch commented 3 years ago

You need to feed VCC line with +12 V from external power adapter to power the display. Or your display has another power in connector?

For the serial converter, make sure you use RS232 compatible one - TTL (3.3V/5V) will not work with the display without hardware modifications.

eranmes commented 3 years ago

Thanks. The display does have two connectors as you can see and I have a cable for the other connector (which is PoweredUSB). I could power the display from that port but not get any data connection (probably because the power and USB ground lines were not tied).

I do plan to use a USB to RS232 converter so the line voltage levels should not be a problem. It's just the ground that I was wondering about.

ggajoch commented 3 years ago

As far as I remember you can power it from either connector. The ground is connected to every pin, at least it should be. Connect it to both power and data connection. You can make sure by checking it with a multimeter.