| ??? 07/27/05 09:13 Read: times |
#98247 - Ooops Responding to: ???'s previous message |
You're right, it appears later machines used the 8255 though, from what I could glean off Google.
HOWEVER ! I HAVE found, in an old old reference book on the PC, that the 8255 was used for the cassette drive adapter, the speaker and the keyboard (PC end - we know the 8048 was used in the keyboard) One port of the 8255 is used to create a sub-bus, which is used to read from configuration dip-switches or to read the scan code from the keyboard input shift register. Other bits in the device are used to drive the audio speaker cone, read serial data from the audio cassette, control the motor in the audio cassette player modulate the clock input on timer counter channel 2, sense check the latches and configuration dip switches and interface to the keyboard serial interface. Steve |
| 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 |