multiplex displays 16f84
>i have a pic16f84 to play with but have no knowledge on writing code for it.
This is your chance to learn. This is a straightforward project.
>i did find the max7219 can display on upto 8 digits which is perfect but
>that means i need to use the 16f84 to read the binary and output the data
>to the 7219..
Yes. I'v used the max7219 with a PIC.
>I looked at the MAX7219 datasheet and this part does not display hex digits,
>either. it displays some symbols, E, H, L, P, but not regular hex digits.
The 7219 can display hex digits however you have to use it in non-decode mode
and tell it what individual led's to illuminate.
You can finds lots of PIC sourcecode on the web to get started.
1. Drive the 7-segment displays using the PIC. That way you can display the characters any way you want. The trouble is that you do not have many I/O pins on the 16F84 and you want 8 digits multiplexed.
You don't have to multiplex the display. One option is to drive a chain of shift registers,
you just need three PIC pins. There are driver chips with syncronous serial (clock and data pin)
inputs that are easy to drive with a microcontroller.