mc68hc912dg128 Freescale Semiconductor, Inc, mc68hc912dg128 Datasheet - Page 430

• Manufacturer Part Number: mc68hc912dg128
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

EEDIVH — EEPROM Modulus Divider
EEDIVL — EEPROM Modulus Divider
Appendix: MC68HC912DG128A EEPROM
22.4 EEPROM Control Registers
Technical Data
430
1. Loaded from SHADOW word.
1. Loaded from SHADOW word.
RESET:
RESET:
CAUTION:
EEDIV7
Bit 7
Bit 7
—
NOTE:
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.
INT[A] denotes the round down integer value of A. Program/erase cycles
will not be activated when EEDIV = 0.
Freescale Semiconductor, Inc.
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 +/- 2 s pulse.
The EEDIV value is determined by the following formula:
For More Information On This Product,
Appendix: MC68HC912DG128A EEPROM
EEDIV5
—
5
0
0
5
(1)
Go to: www.freescale.com
EEDIV4
—
EEDIV
4
0
0
4
(1)
=
EEDIV3
INT
—
3
0
0
3
(1)
EXTALi
EEDIV2
—
2
0
0
2
(hz) x 35
(1)
EEDIV9
EEDIV1
MC68HC912DG128 — Rev 3.0
10
—
—
1
1
(1)
(1)
6 –
+
0.5
EEDIV8
EEDIV0
Bit 0
—
Bit 0
—
(1)
(1)
MOTOROLA
$00EE
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