MC68HC908RF2MFA Freescale Semiconductor, MC68HC908RF2MFA Datasheet - Page 119

• Manufacturer Part Number: MC68HC908RF2MFA
• Description: IC MCU 2K FLASH 4MHZ 32-LQFP
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908RF2MFA

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: LVD, POR, PWM, RF Mod
• Number Of I /o: 12
• Program Memory Size: 2KB (2K x 8)
• Program Memory Type: FLASH
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.6 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 32-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -
• Connectivity: -

10.4 SIM Counter
10.4.1 SIM Counter During Power-On Reset
10.4.2 SIM Counter During Stop Mode Recovery
10.4.3 SIM Counter and Reset States
10.5 Program Exception Control
MC68HC908RF2 — Rev. 4.0
MOTOROLA
cycles later, the CPU is released from reset to allow the reset vector sequence to
occur. (See
The SIM counter is used by the power-on reset module (POR) and in stop mode
recovery to allow the oscillator time to stabilize before enabling the internal bus
(IBUS) clocks. The SIM counter also serves as a prescaler for the computer
operating properly module (COP). The SIM counter overflow supplies the clock for
the COP module. The SIM counter is 12 bits long and is clocked by the falling edge
of CGMXCLK.
The power-on reset module (POR) detects power applied to the MCU. At
power-on, the POR circuit asserts the signal PORRST. Once the SIM is initialized,
it enables the internal clock generation module (ICG) to drive the bus clock state
machine.
The SIM counter also is used for stop mode recovery. The STOP instruction clears
the SIM counter. After an interrupt, break, or reset, the SIM senses the state of the
short stop recovery bit, SSREC, in the CONFIG register. If the SSREC bit is a 1,
then the stop recovery is reduced from the normal delay of 4096 CGMXCLK cycles
down to 32 CGMXCLK cycles. This is ideal for applications using canned
oscillators that do not require long startup times from stop mode. External crystal
applications should use the full stop recovery time, that is, with SSREC cleared.
External reset has no effect on the SIM counter. See
The SIM counter is free-running after all reset states. See
from Internal Sources
Normal, sequential program execution can be changed in three different ways:
1. Interrupts:
2. Reset
3. Break interrupts
Freescale Semiconductor, Inc.
a. Maskable hardware CPU interrupts
b. Non-maskable software interrupt instruction (SWI)
For More Information On This Product,
Section 8. Low-Voltage Inhibit
System Integration Module (SIM)
Go to: www.freescale.com
for counter control and internal reset recovery sequences.
(LVI).)
System Integration Module (SIM)
10.6.2 Stop Mode
10.3.2 Active Resets
SIM Counter
for details.
Data Sheet
119