Rainbow Electronics ATmega103L - Manual (Page 103)

ATmega603/103
103
7. Any memory location can be verified by using the Read instruction which returns the content at the selected
address at serial output PE1(PDO/TXD).
8. At the end of the programming session, RESET can be set high to commence normal operation.
9. Power-off sequence (if needed): Set XTAL1 to ‘0’ (if a crystal is not used). Set RESET to ‘1’. Turn V CC power off
Table 43 shows the actual delays used in this section.
Please NOTE: The MISO pin is not Hi-Z during serial programming.
Data Polling for the EEPROM
When a new EEPROM byte has been written and is being programmed into the EEPROM, reading the address location
being programmed will give the value P1 (please refer to Table 44.) until the auto-erase is finished, and then the value P2.
At the time the device is ready for a new EEPROM byte, the programmed value will read correctly. This is used to deter-
mine when the next byte can be written. This will not work for the values P1 and P2, so when programming these values,
the user will have to wait for at least the prescribed time
t
WD_EEPROM
(please refer to Table 43) before programming the next
byte. As a chip-erased device contains $FF in all locations, programming of addresses that are meant to contain $FF, can
be skipped. This does not apply if the EEPROM is reprogrammed without chip erasing the device.
Data polling is not implemented for the Flash!
Note: See Errata sheet for latest information.
Table 43. Minimum wait delay before writing the next Flash or EEPROM location
Symbol 3.2V 3.6V 4.0V 5.0V
t
WD_FLASH
56 ms 43 ms 35 ms 22 ms
t
WD_EEPROM
9 ms 7 ms 6 ms 4 ms
Table 44. Read back value during EEPROM polling
Part/Revision P1 P2
TBD TBD TBD