| ??? 03/05/07 15:25 Read: times |
#134304 - so now what has been presented several Responding to: ???'s previous message |
I was just curious. When RESET is held high on a standard 8051 chip, are all port pins set to high-impedance? In other words, can I apply 0V or 5V without a resistor in series to any port pin on the microcontroller without damaging it as long as RESET is high?
What I plan to do is use a couple of 74HC573 latches to hold the address and data from the parallel port, so that while the microprocessor is in reset (reset pin is high), I could program the EEPROM directly from the parallel port. So now what has been presented several times by me and others in your previous threads is finally starting to sink in. Erik |
| Topic | Author | Date |
| the RESET pin | 01/01/70 00:00 | |
| Reset and Inputs | 01/01/70 00:00 | |
| thanks | 01/01/70 00:00 | |
| No, that's not true. | 01/01/70 00:00 | |
| Picky, Picky, Picky | 01/01/70 00:00 | |
| not picky Lynn, you need to read | 01/01/70 00:00 | |
| I stand corrected | 01/01/70 00:00 | |
| after reading the link | 01/01/70 00:00 | |
| not entirely | 01/01/70 00:00 | |
| I got the point | 01/01/70 00:00 | |
| That's funny... | 01/01/70 00:00 | |
| not exactly | 01/01/70 00:00 | |
| Please read again... | 01/01/70 00:00 | |
| Missing the point | 01/01/70 00:00 | |
| It looks quite simple to me | 01/01/70 00:00 | |
| but it is also an output | 01/01/70 00:00 | |
| There's no excuse! | 01/01/70 00:00 | |
of course not! | 01/01/70 00:00 | |
| I agree | 01/01/70 00:00 | |
| She? | 01/01/70 00:00 | |
| haha | 01/01/70 00:00 | |
| You\\\'re allowed to do whatever you want, | 01/01/70 00:00 | |
| Depends... | 01/01/70 00:00 | |
| so now what has been presented several | 01/01/70 00:00 | |
| I did read | 01/01/70 00:00 |