MC68376BGMAB20 Freescale Semiconductor, MC68376BGMAB20 Datasheet - Page 153

• Manufacturer Part Number: MC68376BGMAB20
• Description: IC MCU 32BIT 8K ROM 160-QFP
• Manufacturer: Freescale Semiconductor
• Series: M683xxr

Specifications of MC68376BGMAB20

• Core Processor: CPU32
• Core Size: 32-Bit
• Speed: 20MHz
• Connectivity: CAN, EBI/EMI, SCI, SPI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 18
• Program Memory Type: ROMless
• Ram Size: 7.5K x 8
• Voltage - Supply (vcc/vdd): 4.75 V ~ 5.25 V
• Data Converters: A/D 16x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 160-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -

9.2.1.2 Freeze Operation
9.2.1.3 QSM Interrupts
MC68336/376
USER’S MANUAL
The FRZ[1:0] bits in QSMCR are used to determine what action is taken by the QSM
when the IMB FREEZE signal is asserted. FREEZE is asserted when the CPU32 en-
ters background debug mode. At the present time, FRZ0 has no effect; setting FRZ1
causes the QSPI to halt on the first transfer boundary following FREEZE assertion.
Refer to 4.10.2 Background Debug Mode for more information about background de-
bugging mode.
Both the QSPI and SCI can generate interrupt requests. Each has a separate interrupt
request priority register. A single vector register is used to generate exception vector
numbers.
The values of the ILQSPI and ILSCI fields in QILR determine the priority of QSPI and
SCI interrupt requests. The values in these fields correspond to internal interrupt re-
quest signals IRQ[7:1]. A value of %111 causes IRQ7 to be asserted when a QSM in-
terrupt request is made. Lower field values cause correspondingly lower-numbered
interrupt request signals to be asserted. Setting the ILQSPI or ILSCI field values to
%000 disables interrupts for the respective section. If ILQSPI and ILSCI have the
same non-zero value, and the QSPI and SCI make simultaneous interrupt requests,
the QSPI has priority.
When the CPU32 acknowledges an interrupt request, it places the value in the status
register interrupt priority (IP) mask on the address bus. The QSM compares the IP
mask value to the priority of the request to determine whether it should contend for ar-
bitration priority. Arbitration priority is determined by the value of the IARB field in
QSMCR. Each module that generates interrupts must have a non-zero IARB value.
Arbitration is performed by means of serial contention between values stored in indi-
vidual module IARB fields.
When the QSM wins interrupt arbitration, it responds to the CPU32 interrupt acknowl-
edge cycle by placing an interrupt vector number on the data bus. The vector number
is used to calculate displacement into the CPU32 exception vector table. SCI and
QSPI vector numbers are generated from the value in the QIVR INTV field. The values
of bits INTV[7:1] are the same for QSPI and SCI. The value of INTV0 is supplied by
the QSM when an interrupt request is made. INTV0 = 0 for SCI interrupt requests;
INTV0 = 1 for QSPI interrupt requests.
At reset, INTV[7:0] is initialized to $0F, the uninitialized interrupt vector number. To
enable interrupt-driven serial communication, a user-defined vector number must be
written to QIVR, and interrupt handler routines must be located at the addresses point-
ed to by the corresponding vector. Writes to INTV0 have no effect. Reads of INTV0
return a value of one.
Refer to SECTION 4 CENTRAL PROCESSOR UNIT and SECTION 5 SYSTEM IN-
TEGRATION MODULE for more information about exceptions and interrupts.
QUEUED SERIAL MODULE
MOTOROLA
9-3