I'd like to multiplex a 3digit 7seg led display and lcd data lines together.
I need 8 i/o for the led segments and decimal point, I'd like to use the same 8 i/o as the LCD data lines.
figuring the LCD wont act on the data until the EN pin is toggled, and the
LED displays wont show anything until the corresponding digit lines are lowered. (common cathode)
using an 877a, lcd/led data PortD, lcd rs&en on portc (4&5?) and the 7seg leds on portE(0-2). I figure I can use lcdout in pbp to send data to the lcd, and use a timer interupt for an asm led refresh..
neither would be in use at the same time? (I could even disable interrupts during LCD writes if needed, shouldn't blank the digit displays too long, and re-enable them after the lcd write)
anyone see a problem with my logic or doing this?
I was going to try and do assembly for the led's but as I know zilch in assembly, what I thought would be fairly simple, (in asm move digit data variable from pbp to portd and lower corresponding digit portE pin), um, isn't. lol so would probably use DT's instant interupts and do that in PBP as well.
it seems too logical, I must be missing something as I cant find information on it being done anywhere.
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