| ??? 06/12/05 12:46 Read: times |
#94719 - more Responding to: ???'s previous message |
Vijayganesh
for using eeprom at first disable 8255 then enable eeprom and for using 8255 at first disable eeprom then enable 8255 Anyway,What kind of eeprom do you use? See datasheet to find what time takes to release output by eeprom after disabling it or what port is common for eeprom and 8255(data bus)? if port 0 is used,maybe you forget pullups, are you sure all pins (in common bus)work proper? and are you sure 8255 is not damaged? Mehdi |
| Topic | Author | Date |
| external memory access problem | 01/01/70 00:00 | |
| my first suggestion.... | 01/01/70 00:00 | |
| actually i tried in single instruction | 01/01/70 00:00 | |
| more | 01/01/70 00:00 | |
| Relic Chips Are Slow | 01/01/70 00:00 | |
| Memory Map IT !! | 01/01/70 00:00 | |
| and then you may get others | 01/01/70 00:00 | |
| Such AS ?? | 01/01/70 00:00 | |
| with the '51 | 01/01/70 00:00 | |
| 8085/805x <=>8255 | 01/01/70 00:00 | |
| to slow, too low | 01/01/70 00:00 | |
really need more info to be helpful | 01/01/70 00:00 | |
| Query | 01/01/70 00:00 | |
| re query | 01/01/70 00:00 |