| ??? 04/29/11 09:43 Read: times |
#182094 - NE555 Responding to: ???'s previous message |
I cannot find find the MAX 809 in local component market. So I tried to experiment with other IC. I made an astable (free running) multivibrator with NE555 with on period of 10 minutes and off period of 1µS. I connected the output of the 555 to the Reset input of 80C535, so I used the off state as reset pulses.
I gave it a try, and after ten minutes the 80C535 started, so the 555 had successfully reset it. It worked!! It displayed Welcome Message and the menu, and responsed to my commands appropriately. Everything worked just fine. Ten minutes elapsed and it resetted, to again diplayed the Welcome Message. Afterwards it works again perfectly until the next reset. So I am sure that it needed a clean reset pulse at start, and the MAX809 will do it right. IC suppliers in China have it, maybe I have to import it from one of them eventually. While waiting, I would like to look for a circuit which can send a single pulse, preferably with a delay at power up. I thank you very much for your advices. Any more suggestion or comment will be appreciated. |
| Topic | Author | Date |
| Is 80C535 Compatible with 80C31? | 01/01/70 00:00 | |
| do not use pin numbers | 01/01/70 00:00 | |
| Supervisor Chip | 01/01/70 00:00 | |
| you say you want to test chips | 01/01/70 00:00 | |
| Reset Circuitry for 80C535 | 01/01/70 00:00 | |
| Timing | 01/01/70 00:00 | |
| probably because ... | 01/01/70 00:00 | |
| Supervisor/Watchdog Timer chip | 01/01/70 00:00 | |
| No timer needed to kick watchdog | 01/01/70 00:00 | |
| The internal Watchdog Timer | 01/01/70 00:00 | |
| good choice | 01/01/70 00:00 | |
| NE555 | 01/01/70 00:00 | |
| 8051 and 555 reset | 01/01/70 00:00 | |
| 555 Reset circuitry | 01/01/70 00:00 | |
| bad choice | 01/01/70 00:00 | |
| Reset Supervisor | 01/01/70 00:00 | |
| there are other possibilities | 01/01/70 00:00 | |
Other source | 01/01/70 00:00 | |
| did the datasheet not say so? | 01/01/70 00:00 | |
| It says so | 01/01/70 00:00 | |
| would it not be a good idea to do so before ... | 01/01/70 00:00 | |
| explain a bit about the nessecity of Supervisor Chip | 01/01/70 00:00 |