MC68332ACFC25 Freescale Semiconductor, MC68332ACFC25 Datasheet - Page 157

• Manufacturer Part Number: MC68332ACFC25
• Description: IC MCU 32BIT 25MHZ 132-PQFP
• Manufacturer: Freescale Semiconductor
• Series: M683xxr

Specifications of MC68332ACFC25

• Core Processor: CPU32
• Core Size: 32-Bit
• Speed: 25MHz
• Connectivity: EBI/EMI, SCI, SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 15
• Program Memory Type: ROMless
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 132-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

7.2.6 Parameter RAM
7.3 TPU Operation
7.3.1 Event Timing
MC68332
USER’S MANUAL
Parameter RAM occupies 256 bytes at the top of the system address map. Channel
parameters are organized as 128 16-bit words. Although all parameter word locations
in RAM can be accessed by all channels, only 100 are normally used: channels 0 to
13 use six parameter words, while channels 14 and 15 each use eight parameter
words. The parameter RAM address map in APPENDIX D REGISTER SUMMARY
shows how parameter words are organized in memory.
The host CPU specifies function parameters by writing the appropriate RAM address.
The TPU reads the RAM to determine channel operation. The TPU can also store in-
formation to be read by the CPU in RAM. Detailed descriptions of the parameters re-
quired by each time function are beyond the scope of this manual. Refer to the TPU
Reference Manual (TPURM/AD) for more information.
For pre-programmed functions, one of the parameter words associated with each
channel contains three channel control fields. These fields perform the following func-
tions:
PSC —
PAC —
TBS —
All TPU functions are related to one of the two 16-bit time bases. Functions are syn-
thesized by combining sequences of match events and capture events. Because the
primitives are implemented in hardware, the TPU can determine precisely when a
match or capture event occurs, and respond rapidly. An event register for each chan-
nel provides for simultaneity of match/capture event occurrences on all channels.
When a match or input capture event requiring service occurs, the affected channel
generates a service request to the scheduler. The scheduler determines the priority of
the request and assigns the channel to the microengine at the first available time. The
microengine performs the function defined by the content of the control store or emu-
lation RAM, using parameters from the parameter RAM.
Match and capture events are handled by independent channel hardware. This pro-
vides an event accuracy of one time-base clock period, regardless of the number of
channels that are active. An event normally causes a channel to request service. How-
ever, before an event can be serviced, any pending previous requests must be ser-
viced. The time needed to respond to and service an event is determined by the
number of channels requesting service, the relative priorities of the channels request-
ing service, and the microcode execution time of the active functions. Worst-case
Forces the output level of the pin.
For input capture, PAC specifies the edge transition to be detected. For out-
put comparison, PAC specifies the logic level to be output when a match oc-
curs.
Specifies channel direction (input or output) and assigns a time base to the
input capture and output compare functions of the channel.
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TIME PROCESSOR UNIT
7-3