ISE Electronics CU40026SCPB-S 2.0 code example for AVR ATmega

Here is a piece of example code written in WinAVR C for Atmel AVR ATmega128/ATmega2561 to control the CU40026SCBP-S 2.0 VFD from ISE Electronics (Noritake). This display uses a different protocol compared to the common Hitachi-based displays.

The code is rather straight-forward: a single example program written in WinAVR C. All display functions are put in subroutines and the code is well commented. For the debugging and testing, I used one of my ATmega128-boards with an ATmega2561 attached, running with a 16 MHz crystal. The board was powered from the USB-port but the VFD from a separate power supply. This beast for display draws almost 1 A at +5 V in worst case. A standard 7805 regulator needs a rather beefy cooling to avoid overheating. A switching PSU would be a better selection...

My code is based on the datasheet for the CU40026SCPB-S20A that is not the same display but very similar. The instruction set is identical and all commands seems to be the same. The difference between these two displays are the data connection. The S20A-model does have the cable connector mounted at the same side as the glass panel. This is the opposite of the S 2.0 model, where the connector is at the back side of the display (component side). The pin numbering in the datasheet works fine for this display but observe the position (note the typo: pin 1 is D7, nothing else) - ignore the picture in the datasheet! It is the numbering at the PCB that works:

Regarding the source, it is free for everyone to use it for any purpose. Convert it to other microcontrollers if you like (I can host the alternatives here if you like) and add features and functions to improve it.

Development setup using the ATmega128 board

The 5 V regulator needs some serious cooling - it runs rather hot