paulc@boulder.Colorado.EDU (Paul Connally) (06/28/89)
Many thanks to all those who responded to my posting. All the solutions I received were very enlightening but I have one final question to this problem. I've decided to purchase a BCC-180 multitasking single board computer from Circuit Cellar Ink. The reason for this is that I have some other processes that I'll definitely need it for (I know it would be a waste just to program LED's with it!). It has 48-bits of parallel I/O which will be plenty to multiplex the LED segments with. My question is, can I directly connect the anodes/cathodes , 74148 encoder, and the 7445 decoder to the parallel I/O lines. The chips that the CPU (an HD64180) uses for these are 8255's. Or am I going bout this entirely wrong in connecting to the parallel I/O? The CPU board also has an 8-bit BCC-bus, 2 asynch. serial ports, and 1 clocked serial port. Paul Connally paulc@boulder.colorado.edu University of Colorado High Voltage Electron Microscope Lab MCDB - Box 347 "A higher potential for Boulder, CO 80309 better penetration."
mmm@cup.portal.com (Mark Robert Thorson) (06/29/89)
The simplest output (though an expensive one) is through a serial interface. There are many LED and LCD modules which have a one-line display which receive data as an ASCII-encoded TTL signal. This eliminates the need for your computer to scan the display 30 times per second.