MC68HC908AS32A Datasheet, PDF (46/280 Pages) Freescale Semiconductor, Inc – Microcontrollers

Memory
Table 2-4. EEPROM Program/Erase Mode Select
EEBPx
0
EERAS1
0
EERAS0
0
Mode
Byte program
0
0
1
Byte erase
0
1
0
Block erase
0
1
1
Bulk erase
1
X
X = don’t care
X
No erase/program
EELAT — EEPROM Latch Control
This read/write bit latches the address and data buses for programming the EEPROM array. EELAT
cannot be cleared if EEPGM is still set. Reset clears this bit.
1 = Buses configured for EEPROM programming or erase operation
0 = Buses configured for normal operation
AUTO — Automatic Termination of Program/Erase Cycle
When AUTO is set, EEPGM is cleared automatically after the program/erase cycle is terminated by
the internal timer. See note D for 2.8.1.7 EEPROM Programming, 2.8.1.8 EEPROM Erasing, and
19.11.2 EEPROM Memory Characteristics.
1 = Automatic clear of EEPGM is enabled
0 = Automatic clear of EEPGM is disabled
EEPGM — EEPROM Program/Erase Enable
This read/write bit enables the internal charge pump and applies the programming/erasing voltage to
the EEPROM array if the EELAT bit is set and a write to a valid EEPROM location has occurred. Reset
clears the EEPGM bit.
1 = EEPROM programming/erasing power switched on
0 = EEPROM programming/erasing power switched off
NOTE
Writing 0s to both the EELAT and EEPGM bits with a single instruction will
clear EEPGM only to allow time for the removal of high voltage.
2.8.2.2 EEPROM Array Configuration Register
The EEPROM array configuration register configures EEPROM security and EEPROM block protection.
This read-only register is loaded with the contents of the EEPROM nonvolatile register (EENVR) after a
reset.
Address: $FE1F
Bit 7
6
5
4
3
2
Read: UNUSED UNUSED UNUSED EEPRTCT EEBP3 EEBP2
Write:
Reset:
Contents of EENVR ($FE1C)
= Unimplemented
1
EEBP1
Bit 0
EEBP0
Figure 2-5. EEPROM Array Configuration Register (EEACR)
Bit 7–5 — Unused Bits
These read/write bits are software programmable but have no functionality.
MC68HC908AS32A Data Sheet, Rev. 2.0
46
Freescale Semiconductor