| ??? 07/19/06 08:12 Modified: 07/19/06 08:26 Read: times |
#120549 - Ideas Responding to: ???'s previous message |
hi,
Matthias Arndt said:
I have the T89C51CC02 working
Please always indicate full part name: is it T89C51CC02CA, T89C51CC02UA, AT89C51CC02UA etc... Derivatives with CA at the end of name contain CAN-bootloader while UA use UART bootloader. Indeed, you may replace factory bootloader with parallel programmer due it is placed into additional on-chip flash. Now about trouble. Next document: http://www.atmel.com/dyn/resources/prod_documents/doc4223.pdf describes UART bootloader and its hardware conditions. At page 6 it says: Note: The BLJB must be at 0 (programmed) to be able to restart the bootloader. If the BLJB is equal to 1 (unprogrammed) only the hardware parallel programmer can change this bit (see T89C51CC02 Datasheet for more detail). Here we may found that AT89C51CC02 uses totally different way to run bootloader compared to AT89C51CC01/03. Both AT89C51CC01 and AT89C51CC03 check for hardware condition before BLJB and if so then they are trully vectored to bootloader during hardware boot process. Opposite it, AT89C51CC02 hardware checks only for BLJB. And only if it is programmed (set to 0) then ports` states conditions are checked by software (by early-detector part of bootloader). BLJB NOT enabled - Galep asks to enable, I assume it has to be disabled to work from reading the data sheet.
No, just DO program this bit and it should start to work. Regards, Oleg |
| Topic | Author | Date |
| T89C51CC02 UART Bootloader Hardware conditions | 01/01/70 00:00 | |
| Reset ? | 01/01/70 00:00 | |
| Reset circuit | 01/01/70 00:00 | |
| Ooips | 01/01/70 00:00 | |
| proper reset? | 01/01/70 00:00 | |
| they all do | 01/01/70 00:00 | |
| RC reset is for toys. | 01/01/70 00:00 | |
Exactly. | 01/01/70 00:00 | |
| Ideas | 01/01/70 00:00 | |
| part | 01/01/70 00:00 | |
| problem solved! | 01/01/70 00:00 |