| ??? 04/20/07 05:42 Modified: 04/20/07 05:44 Read: times |
#137593 - Please explain ... What do you mean? Responding to: ???'s previous message |
Avishek Kumar said:
All that we have discussed if fine and good.
But Pls see the very first thread, I have not got the answer yet? For cross reference i am giving again 1) I am not able to check the ALE signals. I have previously checked this signal and it was comming. But now it is not comming. But the controller is working. I am using MOVX @R0,A instruction. The way in which you do this is (1) power-down the circuit (2) attach the ground strap of your oscilloscope to a valid and low-impedance ground pin. (3) attach the oscillsocope to ALE of your address latch (pin 11, assuming it's a 74xx373 or 74xx573 (4) adjust the trigger level to somewhere between Vcc and Gnd, with a positive slope. (5) set the timebase to 50 ns/division. You should now be able to observe the behavior of ALE. If not, your circuit is either miswired or something's defective. It's up to you to figure out which. 2)
One more thing that i am using 33Mhz xtal osc. My doubt is what value of resistance should be connected between oscll. output and input pin of controller. Normally a series resistance is put. I want to know the logic, reason and criteria of putting appropriate resistance. Tell us, please, why you believe you should have a resistor anywhere in this part of the circuit. The datasheet doesn't recommend it. The user guide doesn't recommend it. Why do you believe that there should be a resistor anywhere in this circuit? When I use an external oscillator, which I do all the time, I simply drive the XTAL1 pin. You can, if you like, ignore pin 19. RE |
| Topic | Author | Date |
| DS89C430 - - - - -- ALE SIGNAL | 01/01/70 00:00 | |
| Please explain... | 01/01/70 00:00 | |
| explained here | 01/01/70 00:00 | |
| please explain | 01/01/70 00:00 | |
| he probably uses an external crystal oscillator... | 01/01/70 00:00 | |
| Oscillator Feedback Resistor | 01/01/70 00:00 | |
| a thought and a question | 01/01/70 00:00 | |
| There will be ALE on MOVX cycles | 01/01/70 00:00 | |
| pls read this | 01/01/70 00:00 | |
| That\'s not what I said ... | 01/01/70 00:00 | |
| Is this all about 'running without a crystal'? | 01/01/70 00:00 | |
| still at same stage | 01/01/70 00:00 | |
| Please explain ... What do you mean? | 01/01/70 00:00 | |
| Reflections upon your described predicament | 01/01/70 00:00 | |
| do you think he's using a 'scope? | 01/01/70 00:00 | |
| The rigth person | 01/01/70 00:00 | |
late response ... | 01/01/70 00:00 |