ST72F521AR9TC STMicroelectronics, ST72F521AR9TC Datasheet - Page 65

• Manufacturer Part Number: ST72F521AR9TC
• Description: IC MCU 8BIT 60K FLASH 64-TQFP
• Manufacturer: STMicroelectronics
• Series: ST7r

Specifications of ST72F521AR9TC

• Core Processor: ST7
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: CAN, I²C, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 48
• Program Memory Size: 60KB (60K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 3.8 V ~ 5.5 V
• Data Converters: A/D 16x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 64-TQFP, 64-VQFP
• For Use With: 497-6453 - BOARD EVAL BASED ON ST7LNBX
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

PWM AUTO-RELOAD TIMER (Cont’d)
Input capture function
This mode allows the measurement of external
signal pulse widths through ARTICRx registers.
Each input capture can generate an interrupt inde-
pendently on a selected input signal transition.
This event is flagged by a set of the corresponding
CFx bits of the Input Capture Control/Status regis-
ter (ARTICCSR).
These input capture interrupts are enabled
through the CIEx bits of the ARTICCSR register.
The active transition (falling or rising edge) is soft-
ware programmable through the CSx bits of the
ARTICCSR register.
The read only input capture registers (ARTICRx)
are used to latch the auto-reload counter value
when a transition is detected on the ARTICx pin
(CFx bit set in ARTICCSR register). After fetching
the interrupt vector, the CFx flags can be read to
identify the interrupt source.
Note: After a capture detection, data transfer in
the ARTICRx register is inhibited until it is read
(clearing the CFx bit).
The timer interrupt remains pending while the CFx
flag is set when the interrupt is enabled (CIEx bit
set). This means, the ARTICRx register has to be
read at each capture event to clear the CFx flag.
The timing resolution is given by auto-reload coun-
ter cycle time (1/f
Note: During HALT mode, if both input capture
and external clock are enabled, the ARTICRx reg-
ister value is not guaranteed if the input capture
pin and the external clock change simultaneously.
Figure 41. Input Capture Timing Diagram
ICRx REGISTER
ARTICx PIN
COUNTER
CFx FLAG
COUNTER
f
COUNTER
).
01h
02h
xxh
03h
04h
External interrupt capability
This mode allows the Input capture capabilities to
be used as external interrupt sources. The inter-
rupts are generated on the edge of the ARTICx
signal.
The edge sensitivity of the external interrupts is
programmable (CSx bit of ARTICCSR register)
and they are independently enabled through CIEx
bits of the ARTICCSR register. After fetching the
interrupt vector, the CFx flags can be read to iden-
tify the interrupt source.
During HALT mode, the external interrupts can be
used to wake up the micro (if the CIEx bit is set).
05h
INTERRUPT
04h
06h
07h
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