| ??? 07/26/05 14:34 Read: times |
#98166 - Actually.... Responding to: ???'s previous message |
Jan,
The PC did have an 8255 and a 8254 timer. It's amazing how the mere mention of an 8255 sends some people over the edge and causes their eyesight to glaze over. Sure they're old and I doubt if I'd choose to use one in a new design, but if they were the things I had on hand and they were easy to get, why not use them at a pinch. I've just been given a project where I have to upgrade the micros in about 30 boards with a 8751 and a 8255. I could redesign the boards but the cost would be over the top. So, I'm stuck with the 8255 and an equally obsolete serial chip. I'm sure I'll get it all working regardless of the antiquity! The positive side of working with an old chip is that at least the people get a chance of doing some real interfacing of peripheral chips and they may just have to read the datasheet to figure it out! |
| Topic | Author | Date |
| 8255 interfacing problem | 01/01/70 00:00 | |
| well.. | 01/01/70 00:00 | |
| 8255 interface problem | 01/01/70 00:00 | |
| If you must use 8255 | 01/01/70 00:00 | |
| My datasheet says..... | 01/01/70 00:00 | |
| Settle Erik! | 01/01/70 00:00 | |
| 8255 problem | 01/01/70 00:00 | |
| hardware | 01/01/70 00:00 | |
| adding to Steve.. | 01/01/70 00:00 | |
| Comment | 01/01/70 00:00 | |
| Relic | 01/01/70 00:00 | |
| that was not 8255 | 01/01/70 00:00 | |
| Actually.... | 01/01/70 00:00 | |
| ot: 825x in PC | 01/01/70 00:00 | |
| Parallel port | 01/01/70 00:00 | |
| NOoooooooooooooooooooo | 01/01/70 00:00 | |
| Ooops | 01/01/70 00:00 | |
| OK I give it up! :-) | 01/01/70 00:00 | |
| Just like | 01/01/70 00:00 | |
| 8255 in original PC | 01/01/70 00:00 | |
| If I did not keep up with the times and | 01/01/70 00:00 | |
| Do your kids drive Segway? | 01/01/70 00:00 | |
| the real problem is not that the 82xx is | 01/01/70 00:00 | |
| Erik - A history lesson | 01/01/70 00:00 | |
| ok, even further back | 01/01/70 00:00 | |
| Picky, picky | 01/01/70 00:00 | |
| are we getting there now? | 01/01/70 00:00 | |
Oh altight then :-) | 01/01/70 00:00 | |
| More info needed | 01/01/70 00:00 | |
| Pull up resistors. | 01/01/70 00:00 | |
| Pullups | 01/01/70 00:00 | |
| no can do | 01/01/70 00:00 | |
| Yes he can! | 01/01/70 00:00 | |
| does not make it current | 01/01/70 00:00 | |
| my opinion... | 01/01/70 00:00 | |
| did you not read | 01/01/70 00:00 | |
| Nope | 01/01/70 00:00 | |
| 8255 PROBLEM | 01/01/70 00:00 | |
| 10 Points | 01/01/70 00:00 |