| ??? 02/21/07 14:20 Read: times |
#133423 - Internal IAP with external code Responding to: ???'s previous message |
You can execute internal IAP calls with external code in the P89C668 with /EA low.
Once you set the ENBOOT bit, you can call the IAP routines from your external code. When that happens, /PSEN stops, and ports 0 and 2 become FFh. When the routine is done, normal operation resumes. It is similar to the internal / external operation with 8K / 16K / 32K devices. Think of it as a 64K / 1K split, though with the 64K outside, and the 1K inside. |
| Topic | Author | Date |
| 89v51 IAP using ext code PROM | 01/01/70 00:00 | |
| No | 01/01/70 00:00 | |
| how do you do that? | 01/01/70 00:00 | |
| It runs on AT89C51 and P89C51 | 01/01/70 00:00 | |
| Internal IAP with external code | 01/01/70 00:00 | |
ah so... | 01/01/70 00:00 |