ATmega8(L)
Reading the Signature The algorithm for reading the Signature bytes is as follows (refer to “Programming the Flash” on
Bytes
page 222 for details on Command and Address loading):
1. A: Load Command “0000 1000”
2. B: Load Address Low byte (0x00 - 0x02)
3. Set OE to “0”, and BS1 to “0”. The selected Signature byte can now be read at DATA.
4. Set OE to “1”
Reading the
Calibration Byte
The algorithm for reading the Calibration bytes is as follows (refer to “Programming the Flash” on
page 222 for details on Command and Address loading):
1. A: Load Command “0000 1000”
2. B: Load Address Low byte, (0x00 - 0x03)
3. Set OE to “0”, and BS1 to “1”. The Calibration byte can now be read at DATA
4. Set OE to “1”
Parallel Programming Figure 109. Parallel Programming Timing, Including some General Timing Requirements
Characteristics
tXLWL
tXHXL
XTAL1
tDVXH
tXLDX
Data & Contol
(DATA, XA0/1, BS1, BS2)
tBVPH
tPLBX
t BVWL
tWLBX
PAGEL
tPHPL
tWL WH
WR
tPLWL
WLRL
RDY/BSY
tWLRH
Figure 110. Parallel Programming Timing, Loading Sequence with Timing Requirements(1)
LOAD DATA
LOAD ADDRESS
(LOW BYTE)
LOAD DATA
(LOW BYTE)
LOAD DATA
(HIGH BYTE)
LOAD ADDRESS
(LOW BYTE)
tXLPH
tXLXH
tPLXH
XTAL1
BS1
PAGEL
DATA
ADDR0 (Low Byte)
DATA (Low Byte)
DATA (High Byte)
ADDR1 (Low Byte)
XA0
XA1
Note:
1. The timing requirements shown in Figure 109 (that is, tDVXH, tXHXL, and tXLDX) also apply to
loading operation
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2486AA–AVR–02/2013
ATMEL [ ATMEL ]
