| ??? 10/09/07 21:00 Modified: 10/09/07 21:01 Read: times |
#145561 - I tried and here is the solution... Responding to: ???'s previous message |
... use ANL FCF,#0xFC to switch to bootblock.
The point is, that you need both bits (SWR and BSEL) zero to "see" the bootblock; and SWR is one because that's how the bootloader switches to user block after timing out waiting for the "U". It took me a hour (plus 30 min to pull a zombie board with the 'V51' off the box and revive it) just because I am a stupid showoff and went the trial-and-error method (switching on and off a LED after each step and similar "embedded printf" stuff) rather than look into the datasheet and/or my own proven good code, which would take maybe 5 minutes... JW PS. You should end in an endless loop, otherwise the return from main() will cause "funny" behaviour - see http://www.8052.com/faqs.phtml?FAQ=143904 |
| Topic | Author | Date |
| IAP with the P89V51RD2 | 01/01/70 00:00 | |
| MOV ACC, 55H? | 01/01/70 00:00 | |
| Change has no effect | 01/01/70 00:00 | |
| post the relevant parts... | 01/01/70 00:00 | |
| Here\'s the simplest program | 01/01/70 00:00 | |
| how do you know this does not work? | 01/01/70 00:00 | |
| Displayed memory | 01/01/70 00:00 | |
| I tried and here is the solution... | 01/01/70 00:00 | |
Works perfectly! | 01/01/70 00:00 |