Oops, well I'm talking beyond my knowledge level here. I was thinking of the standard LCD Hitachi interface. I guess we'd be thinking TFT or something for the graphical screen. Not sure what the standards are there for I/O.
I took a quick look at Adafruit and I see one that requires 14 (!) lines, but another that uses SPI says it just needs 4 or 5 digital pins to send data to the display.
Regarding multiplexing pins, I'm looking at my PIC log power board and I see that I have one pin that's used for data out to the LCD and for UART transmit, while another has three uses: data to LCD, UART receive, and DDS clock.
73-
Nick, WA5BDU
JIm, you might like to look at this project (kit) which sells for about $100 all up with display for inspiration. It can be bought with PC interface only for half that or add the seperate display driven serially. Or, a bluetooth pcb that displays on an Android phone. Schematics are available on the page also.
I've been puzzling over how to configure the SSNA so at least it doesn't **prevent** the addition of a display. Better Arduino heads than mine may be needed for advice and counsel here.
I'm going under the presumption that the UNO has 14 digital I/O lines available. The DDS interface uses 4 (D8 - D11 at this time, but that can change).
Most LCD displays (parallel interface) need 8 data lines, an enable, a read/write line, and a clock. That adds up to 15. That may preclude the addition of a parallel display on the UNO. Of course a (more costly) serial LCD would solve that problem. And the serial TX and RX lines are not used by the SSNA.
