Rainbow Electronics AT90S8515 - Manual (Page 83)

83
AT90S8515
0841G–09/01
Figure 62. 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. (AT90S8515 only) 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. (AT90S8515 only) 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”.
Programming the Fuse Bits The algorithm for programming the Fuse bits is as follows (refer to “Programming the
Flash” for details on command and data loading):
1. A: Load Command “0100 0000”.
2. D: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
DATA HIGH DATA
XA1
XA0
BS
XTAL1
WR
RDY/BSY
RESET +12V
OE