In spite of prevailing evidence, not all LED smart displays were made by Litronix and Hewlett-Packard. RFT, based in Germany, also made smart displays such as this one, the VQC10.
Packaged in an attractive red molded epoxy package, the VQC10 has four characters, each containing 35 LED dies arranged in a 5x7 matrix.
Unlike many other smart displays, the VQC10 has no built in character driver or other advanced features.
The display uses an extremely convoluted control scheme, rows across all digits are ganged together and controlled manually, while each column can be selected by sending a 9 bit address in parallel to the display's driver circuitry.
The home experimenter should take note that the VQC10 has wider pin spacing than most DIP LED displays, and will not fit in a conventional breadboard or socket.
Hi Tom, thank you for replay, as per my experience, it is nothing very advanced, i did some led blinking, DHT with BT adapters, and i could swear i did posted loooong time ago on this forum but for some reason none of my credentials worked, thus new account
i have few uno’s, mega’s, nano’s that i did some simple programming for my son (like police lights acrivated by remote - i know, very simple, but that is my level :p)
since I’m a sucker on led/vfd/nixie/numitron displays, it was too good of a deal to pass on the flea market ( less than a dollar/euro per piece). But i guess i’ll go with different way, as you suggested, easier way :).
Maybe one day I’ll learn enough to tame this one, and maybe do a wristwatch
I don't think it would be too difficult to drive, but an interesting challenge!
It looks like you could drive it with 16 pins and 7 series resistors. Unfortunately because of the design, it looks as though you will have to use a 1 to 20 multiplex ratio (i.e. column-at-a-time), which will not be very bright. You could try a 1 to 7 ratio (i.e. row-at-a-time), but you would need high-side drivers for the anodes, and you would be connecting 20 LEDs in parallel without individual series resistors, which is not advised.
Hello! I have two VQC10 bought many years ago. I think I bougt them more than 30 years ago. Recent I discover them in a box. I never comisioning them. They are as new.
Thank of you, I found the old “democratic” Germany datasheet, but it is stupid. I made some tests with VQC10 and I descovered how it works. With new technology, it is easy to use. Arduino is the easyest way.
How it work: put 5V on Z1 to suplly the top row of LED-s. Put on D1,D2,D3,D4 and D5 the LED status you whant. Low for Off, high logic for On. Then strobe pin c.p. corespondind to matrix you display now. Latch of c.p. digit will memorize the D1…D5 status. Now you can change the D1 … D5, the LEDs of first row will not change.
I tested a VQC10 only on a 5V power supply. When I’ll write an Arduino program for this old and very nice display, I’ll come back
Sory, yesturday I made some tests only with a power supplay to understand how the VQC10 works. I haven’t yet a schematic diagram and a code. I just light a row by Z conection then I descover the logical control of columns. I draw a first timing diagram.
way :).
