| ??? 11/30/06 14:34 Read: times |
#128749 - 1 bit per segment! Responding to: ???'s previous message |
Ralph Sack said:
I still don't know how Dan K. was driving the 7 segment display. Normally displays are driven with sn7447 common cathode or... I don't know about "normally" - bit of a sweeping generalisation there, eh! The 7447 et al are, as you say, BCD-to-7-Segment decoders; but, if you don't have BCD, why would you use one? If you're using a microcontroller, why waste a separate chip? An 8-bit port has exactly the right number of lines to drive a 7-segment digit - one bit for each segment (including the DP). You'd need to check both the per-pin and per-port current ratings but, if they're OK, there's no reason why you shouldn't connect the display direct to the port pins (with suitable current-limits, of course). You then have software in the micro to activate the appropriate set of segments for the required digit - a lookup table is ideal. |
| Topic | Author | Date |
| Pseudo Random Number Generator Questions | 01/01/70 00:00 | |
| Ok figured it out | 01/01/70 00:00 | |
| i dunno are they all ignoring you? | 01/01/70 00:00 | |
| 8 Segments | 01/01/70 00:00 | |
| Spelling error | 01/01/70 00:00 | |
| 1 bit per segment! | 01/01/70 00:00 | |
| Here's one I prepared earlier... | 01/01/70 00:00 | |
| I light 7 segment led | 01/01/70 00:00 | |
| Unethical! | 01/01/70 00:00 | |
| That not what I am saying | 01/01/70 00:00 | |
| this is ridiculoss | 01/01/70 00:00 | |
| I spent hour no answers | 01/01/70 00:00 | |
| seven segment | 01/01/70 00:00 | |
| It is... | 01/01/70 00:00 | |
| Now do the rest | 01/01/70 00:00 | |
| Not Rocket Science! | 01/01/70 00:00 | |
Misleading comments | 01/01/70 00:00 | |
| Looking at program | 01/01/70 00:00 | |
| Your right Jon | 01/01/70 00:00 | |
| Now that is tempting... | 01/01/70 00:00 | |
| A link to the thread | 01/01/70 00:00 | |
| Do it in the forum! | 01/01/70 00:00 |