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Klaus
- 15th April 2008, 02:13
Hi,
I was using a 7-segment display driver/multiplexer IC, the MC14489, with the basic stamp. Now that I have switched to using a PIC18F4550, I'm wondering if I can do without that chip and have the PIC run this also. I'm using a 3x4 keypad to enter data, along with some serial data from shift registers. I think there there is enough I/O to also do the 4 digit, 7 segment control. So my basic question is, would this be a better way to do this, or would I be better off staying with something that worked well with the Stamp.
Thanks,
Klaus

skimask
- 15th April 2008, 02:35
I was using a 7-segment display driver/multiplexer IC, the MC14489, with the basic stamp. Now that I have switched to using a PIC18F4550, I'm wondering if I can do without that chip and have the PIC run this also.
A generic run-of-the-mill parallel LCD can take as few as 6 I/O lines to operate, plus Vdd/Vss. Or you can get a serial-backpack-LCD, 1 line, plus Vdd/Vss. Or you can use shift registers on a couple of outputs and clock the data out to the LCD, 2 lines plus Vdd/Vss.
But if you really must have a 7 segment drive, yes, a small PIC, anything with at least 11 I/O pins can easily handle mux'ing a 7 segment LED. And the more I/O, the more the digits/options.
But the parallel LCD is already directly supported with PBP, so why use 7 segment LEDs?

mister_e
- 15th April 2008, 04:03
Because it's easier to read when you're far.... or simply asked in some instrumentation equipment?
<hr>
With the USB PIC you can handle everything in ONE chip WITHOUT the need for any extra hardware in many case (ok some resistors and maybe some transistors). Yes it's a bit tedious the first time, but once you know how, it's not as this hard.

ANY PIC will also be WAY faster than ANY BasicStamp... and how about their prices ? :D

Be confident, get your hand dirty playing with them... they won't bite you ;)

Klaus
- 15th April 2008, 13:37
Thanks for your response. I thought that that was the way to go, even with my limited experience with micro controllers, and yes, I have to use LED displays because the displays have to be easily seen in a well lit room from a distance.
Klaus