| ??? 12/20/05 13:12 Read: times |
#105587 - if you refer to D4 then Responding to: ???'s previous message |
The o/p of 7805 reads 5VDC
But the LED connected to its o/p through a 500 ohms resistor glows dim. Assuming you have a constant "low" on the port pin: If you refer to D4 then a) what does that datasheet say about max sink current on the port and b) if a) is not the problem you are using an LED that either is too large or too inefficient. I drive my little "show it works" LEDs through 1k and they are not "dim" Erik |
| Topic | Author | Date |
| Add on card programming | 01/01/70 00:00 | |
| please clarify | 01/01/70 00:00 | |
| RE: please clarify | 01/01/70 00:00 | |
| (E)ISA addressing | 01/01/70 00:00 | |
| IOW and IOR | 01/01/70 00:00 | |
| not explicitly | 01/01/70 00:00 | |
| IRQ in EISA slot | 01/01/70 00:00 | |
| interrupt | 01/01/70 00:00 | |
| QBASIC programming | 01/01/70 00:00 | |
| reply | 01/01/70 00:00 | |
| DIP Switch Address Setting in EISA card | 01/01/70 00:00 | |
| DIP switches... | 01/01/70 00:00 | |
| card design enclosed | 01/01/70 00:00 | |
| comparator | 01/01/70 00:00 | |
| QBASIC live and well. | 01/01/70 00:00 | |
| NT - not quite | 01/01/70 00:00 | |
| timing in Win? | 01/01/70 00:00 | |
| QBasic Lives!!! | 01/01/70 00:00 | |
| refer to 'Barry B Brey' | 01/01/70 00:00 | |
| EISA Bus interfacing | 01/01/70 00:00 | |
| beware if (E)ISA bus books | 01/01/70 00:00 | |
| Try this? | 01/01/70 00:00 | |
| Power resistor selection | 01/01/70 00:00 | |
| dont do it | 01/01/70 00:00 | |
| LM317 is an option | 01/01/70 00:00 | |
| Wasteful! | 01/01/70 00:00 | |
| if op can........... | 01/01/70 00:00 | |
| Power! | 01/01/70 00:00 | |
| basic Ohm's law | 01/01/70 00:00 | |
| Trouble shoot | 01/01/70 00:00 | |
| heating | 01/01/70 00:00 | |
| Reply : Heating | 01/01/70 00:00 | |
if you refer to D4 then | 01/01/70 00:00 |