Manual

97
AT90S/LS8535
1041H11/01
Figure 69. Programming the Flash Waveforms (Continued)
Reading the Flash The algorithm for reading the Flash memory is as follows (refer to Programming the
Flash for details on command and address loading):
1. A: Load Command 0000 0010.
2. B: Load Address High Byte ($00 - $0F).
3. C: Load Address Low Byte ($00 - $FF).
4. Set OE
to 0 and BS to 0. The Flash word low byte can now be read at DATA.
5. Set BS to 1. The Flash word high byte can now be read from DATA.
6. Set OE to 1.
Programming the EEPROM The programming algorithm for the EEPROM data memory is as follows (refer to Pro-
gramming the Flash for details on command, address and data loading):
1. A: Load Command 0001 0001.
2. B: Load Address High Byte ($00 - $01).
3. C: Load Address Low Byte ($00 - $FF).
4. D: Load Data Low Byte ($00 - $FF).
5. E: Write Data Low Byte.
Reading the EEPROM The algorithm for reading the EEPROM memory is as follows (refer to Programming the
Flash for details on command and address loading):
1. A: Load Command 0000 0011.
2. B: Load Address High Byte ($00 - $01).
3. C: Load Address Low Byte ($00 - $FF).
4. Set OE
to 0 and BS to 0. The EEPROM data byte can now be read at DATA.
5. Set OE to 1.
DATA HIGH
DATA
XA1
XA0
BS
XTAL1
WR
RDY/BSY
RESET
+12V
OE