MC68HC908AT32 Datasheet, PDF (62/378 Pages) Freescale Semiconductor, Inc – Microcontrollers

Electrically Erasable Programmable ROM (EEPROM)
EEPGM — EEPROM Program/Erase Enable Bit
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 logic 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.
5.3.8 EEPROM Non-Volatile Register and EEPROM Array Configuration Register
The EEPROM non-volatile register (EENVR) and array configuration register (EEACR) are shown in
Figure 5-3 and Figure 5-2.
Address: $FE1C
Bit 7
6
5
4
3
Read:
EERA
Write:
CON2
CON1
CON0 EEBP3
Reset:
PV
PV = Programmed value or 1 in the erased state.
2
EEBP2
1
EEBP1
Figure 5-2. EEPROM Non-Volatile Register (EENVR)
Bit 0
EEBP0
Address:
Read:
Write:
Reset:
$FE1F
Bit 7
EERA
6
CON2
5
CON1
4
CON0
3
EEBP3
2
EEBP2
1
EEBP1
Reset loads bits from EENVR to EEACR
= Unimplemented
Figure 5-3. EEPROM Array Control Register (EEACR)
Bit 0
EEBP0
EERA — EEPROM Redundant Array Bit
This programmable/erasable/read bit in EENVR and read-only bit in EEACR configures the array in
redundant mode. Reset loads EERA from EENVR to EEACR.
1 = EEPROM array is in redundant mode configuration.
0 = EEPROM array is in normal mode configuration.
CONx — MCU Configuration Bits
These read/write bits can be used to enable/disable functions within the MCU. Reset loads CONx from
EENVR to EEACR.
CON2 — Unused
CON1 — Unused
CON0 — EEPROM Security Bit
1 = EEPROM security disabled
0 = EEPROM security enabled
MC68HC908AT32 Data Sheet, Rev. 3.1
62
Freescale Semiconductor