ATTINY13-12SI View Datasheet(PDF) - Atmel Corporation
Part Name
Description
Manufacturer
ATTINY13-12SI Datasheet PDF : 169 Pages
| |||
Atomic Byte Programming
Split Byte Programming
Erase
Write
one to trigger the EEPROM read. The EEPROM read access takes one instruction, and
the requested data is available immediately. When the EEPROM is read, the CPU is
halted for four cycles before the next instruction is executed. The user should poll the
EEPE bit before starting the read operation. If a write operation is in progress, it is nei-
ther possible to read the EEPROM, nor to change the EEARL Register.
Using Atomic Byte Programming is the simplest mode. When writing a byte to the
EEPROM, the user must write the address into the EEARL Register and data into EEDR
Register. If the EEPMn bits are zero, writing EEPE (within four cycles after EEMPE is
written) will trigger the erase/write operation. Both the erase and write cycle are done in
one operation and the total programming time is given in Table 1. The EEPE bit remains
set until the erase and write operations are completed. While the device is busy with
programming, it is not possible to do any other EEPROM operations.
It is possible to split the erase and write cycle in two different operations. This may be
useful if the system requires short access time for some limited period of time (typically
if the power supply voltage falls). In order to take advantage of this method, it is required
that the locations to be written have been erased before the write operation. But since
the erase and write operations are split, it is possible to do the erase operations when
the system allows doing time-critical operations (typically after Power-up).
To erase a byte, the address must be written to EEARL. If the EEPMn bits are 0b01,
writing the EEPE (within four cycles after EEMPE is written) will trigger the erase opera-
tion only (programming time is given in Table 1). The EEPE bit remains set until the
erase operation completes. While the device is busy programming, it is not possible to
do any other EEPROM operations.
To write a location, the user must write the address into EEARL and the data into EEDR.
If the EEPMn bits are 0b10, writing the EEPE (within four cycles after EEMPE is written)
will trigger the write operation only (programming time is given in Table 1). The EEPE bit
remains set until the write operation completes. If the location to be written has not been
erased before write, the data that is stored must be considered as lost. While the device
is busy with programming, it is not possible to do any other EEPROM operations.
The calibrated Oscillator is used to time the EEPROM accesses. Make sure the Oscilla-
tor frequency is within the requirements described in “Oscillator Calibration Register –
OSCCAL” on page 22.
16 ATtiny13
2535B–AVR–01/04
Share Link: 