MC68HC908QY4MDT Freescale Semiconductor, MC68HC908QY4MDT Datasheet - Page 108

no-image

MC68HC908QY4MDT

Manufacturer Part Number
MC68HC908QY4MDT
Description
IC MCU 4K FLASH 8MHZ 16-TSSOP
Manufacturer
Freescale Semiconductor
Series
HC08r
Datasheet

Specifications of MC68HC908QY4MDT

Core Processor
HC08
Core Size
8-Bit
Speed
8MHz
Peripherals
LVD, POR, PWM
Number Of I /o
13
Program Memory Size
4KB (4K x 8)
Program Memory Type
FLASH
Ram Size
128 x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 5.5 V
Data Converters
A/D 4x8b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 125°C
Package / Case
16-TSSOP
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Eeprom Size
-
Connectivity
-

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
MC68HC908QY4MDTE
Manufacturer:
Vishay
Quantity:
5 579
System Integration Module (SIM)
13.4.2.2 Computer Operating Properly (COP) Reset
An input to the SIM is reserved for the COP reset signal. The overflow of the COP counter causes an
internal reset and sets the COP bit in the SIM reset status register (SRSR). The SIM actively pulls down
the RST pin for all internal reset sources.
To prevent a COP module time out, write any value to location $FFFF. Writing to location $FFFF clears
the COP counter and stages 12–5 of the SIM counter. The SIM counter output, which occurs at least
every 4080 BUSCLKX4 cycles, drives the COP counter. The COP should be serviced as soon as possible
out of reset to guarantee the maximum amount of time before the first time out.
The COP module is disabled during a break interrupt with monitor mode when BDCOP bit is set in break
auxiliary register (BRKAR).
13.4.2.3 Illegal Opcode Reset
The SIM decodes signals from the CPU to detect illegal instructions. An illegal instruction sets the ILOP
bit in the SIM reset status register (SRSR) and causes a reset.
If the stop enable bit, STOP, in the mask option register is 0, the SIM treats the STOP instruction as an
illegal opcode and causes an illegal opcode reset. The SIM actively pulls down the RST pin for all internal
reset sources.
13.4.2.4 Illegal Address Reset
An opcode fetch from an unmapped address generates an illegal address reset. The SIM verifies that the
CPU is fetching an opcode prior to asserting the ILAD bit in the SIM reset status register (SRSR) and
resetting the MCU. A data fetch from an unmapped address does not generate a reset. The SIM actively
pulls down the RST pin for all internal reset sources. See
Figure 2-1. Memory Map
for memory ranges.
13.4.2.5 Low-Voltage Inhibit (LVI) Reset
The LVI asserts its output to the SIM when the V
voltage falls to the LVI trip voltage V
. The LVI
DD
TRIPF
bit in the SIM reset status register (SRSR) is set, and the external reset pin (RST) is held low while the
SIM counter counts out 4096 BUSCLKX4 cycles after V
rises above V
. Sixty-four BUSCLKX4
DD
TRIPR
cycles later, the CPU and memories are released from reset to allow the reset vector sequence to occur.
The SIM actively pulls down the (RST) pin for all internal reset sources.
13.5 SIM Counter
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 uses 12 stages for
counting, followed by a 13th stage that triggers a reset of SIM counters and supplies the clock for the COP
module. The SIM counter is clocked by the falling edge of BUSCLKX4.
13.5.1 SIM Counter During Power-On Reset
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 oscillator to drive the bus clock
state machine.
MC68HC908QY/QT Family Data Sheet, Rev. 6
108
Freescale Semiconductor

Related parts for MC68HC908QY4MDT