| ??? 03/24/12 19:33 Modified: 03/24/12 19:41 Read: times |
#186864 - Interrupts, the 8052 & Solenoids |
Hi all,
Designed and built this project on a breadboard and everything worked accordingly but I am now having issues with it on the PCP board. The interrupt is triggered by an external circuit that detects smoke. It is is an edge triggered interrupt - smoke detected, interrupt pin goes low and interrupt routine begins. Problem is - even without this external circuit connected the interrupt is being triggered by the solenoids. The solenoids are driven by the relays. When I disconnect solenoid from circuit and the relays are energised eveything is okay. When I connect the solenoids the following happens; Relay energises and solenoid plunger retracts. It is fine to this point. When the programmed time has elapsed and the relay is no longer energised, the solenoid plunger is released but this then triggers the 89s52's interrupt routine. The solenoids both have their own power and ground. Help please?  |
| Topic | Author | Date |
| Interrupts, the 8052 & Solenoids | 01/01/70 00:00 | |
| Freewheeel diodes | 01/01/70 00:00 | |
| ULN2003a | 01/01/70 00:00 | |
| more than one inductive load here | 01/01/70 00:00 | |
| Solenoids | 01/01/70 00:00 | |
| diode choices | 01/01/70 00:00 | |
| Diodes in ULN2003a | 01/01/70 00:00 | |
| Within this chip | 01/01/70 00:00 | |
| Do I hear... | 01/01/70 00:00 | |
| Irish keypad layout!! | 01/01/70 00:00 | |
| Lack of resistors. | 01/01/70 00:00 | |
Success | 01/01/70 00:00 |