Bascom and AVR, a TIL311 Bitx20 display

For my BITX20 transceiver I wanted something 'different' as frequency display. I remembered I had a few old Texas Instruments TIL311 hexadecimal led displays that seemed suitable. These displays first appeared in the 1970's, they use lots of current (more than the BITX20 in receive...) but being led display have excellent contrast.
Amazingly enough, Texas Instruments still has the datasheet online. Bravo TI!
I wrote a small program for the ATMega8 to read the BITX20 VFO frequency, add a constant IF frequency and display the result. The VFO signal is buffered using a J310 and 2N3904. The buffer output is connected to the T1 input of the ATMega8.
The program uses a constant to determine the count time (app. 100 milliseconds). If you use another chrystal frequency you must change this value. Experiment!
The program then calculates the digits to display and sends these digits to the displays. The A, B, C and D inputs of all display are connected together. The Latch Strobe inputs of all displays are connected to Port C and D of the ATMega8. Although the schematic shows eight diplays, I show the frequency as 0xx.xxxxx foto van het display foto van de counter programma schema

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