| ??? 09/12/10 00:03 Read: times |
#178514 - Even only the layout is a bad joke... Responding to: ???'s previous message |
Nishad said:
I am a newbee,i am working on 89s52.i make a project which is not working.For this project,i go through the site "http://www.kmitl.ac.th/~kswichit...%20S51.htm" If you have a look at the ground routing of the supply decoupling cap or the ISP connector's ground terminal, you will notice that this project is entirely dodgy! Also, the ISP cable has no screening lines between MISO, MOSI and SCK. So, capacitive cross coupling will erode the signal integrity of serial transmission. This the more so because there isn't any series termination at these lines. More, the burden caps of Pierce oscillator have a bad ground connection and will contaminate the signal ground, especially the ISP connector's ground. How this circuit shall work reliably is a mystery. A 40pin-DIL-package micro in such a pcb is a desaster, especially at 33MHz clock speed... This "project" is TRASH, PLAIN BOGUS! The likelihood of success? Not over 5%. Kai Klaas |
| Topic | Author | Date |
| help me plzzzzzzzzzzzz | 01/01/70 00:00 | |
| Re: | 01/01/70 00:00 | |
| did you fall asleep after 'pl' ? | 01/01/70 00:00 | |
| How far did you go through that site? | 01/01/70 00:00 | |
| Possible reason... | 01/01/70 00:00 | |
| More possible reasons - NOT a good beginner's page! | 01/01/70 00:00 | |
| Even only the layout is a bad joke... | 01/01/70 00:00 | |
"works" | 01/01/70 00:00 |