MC912DG128A Motorola, MC912DG128A Datasheet - Page 105

• Manufacturer Part Number: MC912DG128A
• Description: Microcontrollers
• Manufacturer: Motorola

EEDIVH — EEPROM Modulus Divider
EEDIVL — EEPROM Modulus Divider
EEPROM Control Registers
5-eeprom
MOTOROLA
1. Loaded from SHADOW word.
1. Loaded from SHADOW word.
RESET:
RESET:
CAUTION:
EEDIV7
Bit 7
Bit 7
—
0
0
(1)
EEDIV6
—
6
0
0
6
(1)
EEDIV[9:0] — Prescaler divider
An incorrect or uninitialized value on EEDIV can result in overstress of
EEPROM array during program/erase operation. It is also strongly
recommend not to program EEPROM with oscillator frequencies less
than 250 Khz.
Loaded from SHADOW word at reset.
Read anytime. Write once in normal modes (SMODN =1) if EELAT =
0 and anytime in special modes (SMODN =0) if EELAT = 0.
The prescaler divider is required to produce a self-time clock with a
fixed frequency around 28.6 Khz for the range of oscillator
frequencies. The divider is set so that the oscillator frequency can be
divided by a divide factor that can produce a 35 s
The EEDIV value is determined by the following formula:
EEDIV5
—
5
0
0
5
(1)
EEDIV4
—
EEDIV
4
0
0
4
(1)
EEPROM
=
EEDIV3
INT
—
3
0
0
3
(1)
EXTALi
EEDIV2
—
2
0
0
2
(hz) x 35
(1)
EEDIV9
EEDIV1
10
—
—
MC68HC912DT128A Rev 2.0
1
1
(1)
(1)
6 –
EEPROM Control Registers
+
0.5
EEDIV8
EEDIV0
2 s timebase.
Bit 0
—
Bit 0
—
(1)
(1)
EEPROM
$00EE
$00EF
105