MC68711E20CFNE3 Datasheet, PDF (54/242 Pages) –

Operating Modes and On-Chip Memory
EPGM — EPROM/OTPROM/EEPROM Programming Voltage Enable Bit
0 = Programming voltage to EEPROM array switched off
1 = Programming voltage to EEPROM array switched on
During EEPROM programming, the ROW and BYTE bits of PPROG are not used. If the frequency of the
E clock is 1 MHz or less, set the CSEL bit in the OPTION register. Recall that 0s must be erased by a
separate erase operation before programming. The following examples of how to program an EEPROM
byte assume that the appropriate bits in BPROT are cleared.
PROG
LDAB
STAB
STAA
LDAB
STAB
JSR
CLR
#$02
$103B
$XXXX
#$03
$103B
DLY10
$103B
EELAT = 1
Set EELAT bit
Store data to EEPROM address
(for valid EEPROM address see memory
map for each device)
EELAT = 1, EPGM = 1
Turn on programming voltage
Delay 10 ms
Turn off high voltage and set
to READ mode
2.5.1.3 EEPROM Bulk Erase
This is an example of how to bulk erase the entire EEPROM. The CONFIG register is not affected in this
example.
BULKE
LDAB
STAB
STAA
LDAB
STAB
JSR
CLR
#$06
$103B
$XXXX
#$07
$103B
DLY10
$103B
EELAT = 1, ERASE = 1
Set to BULK erase mode
Store data to any EEPROM address (for
valid EEPROM address see memory map
for each device)
EELAT = 1, EPGM = 1, ERASE = 1
Turn on high voltage
Delay 10 ms
Turn off high voltage and set
to READ mode
2.5.1.4 EEPROM Row Erase
This example shows how to perform a fast erase of large sections of EEPROM.
ROWE
LDAB
STAB
STAB
LDAB
STAB
JSR
CLR
#$0E
$103B
0,X
#$0F
$103B
DLY10
$103B
ROW = 1, ERASE = 1, EELAT = 1
Set to ROW erase mode
Write any data to any address in ROW
ROW = 1, ERASE = 1, EELAT = 1, EPGM = 1
Turn on high voltage
Delay 10 ms
Turn off high voltage and set
to READ mode
M68HC11E Family Data Sheet, Rev. 5.1
54
Freescale Semiconductor