| ??? 09/29/05 07:44 Read: times |
#101703 - direction Responding to: ???'s previous message |
Brice Hassenstab said:
Has anyone tried buffering the address and data lines on an 8052 in external mem mode in a 8052 Basic system? I have not as I ported BASIC52 to the 'RD2's exactly in order to avoid the external memories and their interfaces... Brice Hassenstab said:
I have tried AND'ing PSEN and RD to enable the '245 for proper read of all external read's but the system does not boot. And how did you connect the direction pin of '245? I would rather connect the ANDed (or NANDed - depending on the orientation of '245) /PSEN and /RD to the direction pin, and ground the /enable pin. Jan Waclawek |
| Topic | Author | Date |
| Buffering address/data bus Basic-52 | 01/01/70 00:00 | |
| direction | 01/01/70 00:00 | |
| Yes | 01/01/70 00:00 | |
| '573? | 01/01/70 00:00 | |
| 245 | 01/01/70 00:00 | |
| Only need one latch | 01/01/70 00:00 | |
| Re-read this... | 01/01/70 00:00 | |
| negative logic | 01/01/70 00:00 | |
| caqll a spade a spade | 01/01/70 00:00 | |
| Ok... I follow you, but... | 01/01/70 00:00 | |
| 74F623 instead of 74F245 | 01/01/70 00:00 | |
| I'd stick with a 245 | 01/01/70 00:00 | |
74AC623 is also fast | 01/01/70 00:00 | |
| A little clarification | 01/01/70 00:00 | |
| if you are ANDing them it will never wor | 01/01/70 00:00 | |
| How fast is your memory? | 01/01/70 00:00 |