Reading the flash, Programming the eeprom, Reading the eeprom – Rainbow Electronics AT90LS4433 User Manual
Page 90
90
AT90S/LS4433
1042G–AVR–09/02
Figure 64. 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):
A: Load Command “0000 0010”.
B: Load Address High Byte ($00 - $07).
C: Load Address Low Byte ($00 - $FF).
1.
Set OE to “0”, and BS to “0”. The Flash word Low Byte can now be read at
DATA.
2.
Set BS to “1”. The Flash word High Byte can now be read from DATA.
3.
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):
A: Load Command “0001 0001”.
B: Load Address Low Byte ($00 - $FF).
C: Load Data Low Byte ($00 - $FF).
D: 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):
A: Load Command “0000 0011”.
B: Load Address Low Byte ($00 - $FF).
1.
Set OE to “0”, and BS to “0”. The EEPROM data byte can now be read at DATA.
2.
Set OE to “1”.
DATA HIGH
DATA
XA1
XA0
BS
XTAL1
WR
RDY/BSY
RESET
+12V
OE