at90pwm81-16se ATMEL Corporation, at90pwm81-16se Datasheet - Page 169

• Manufacturer Part Number: at90pwm81-16se
• Description: 8-bit Avr Microcontroller With 8k Bytes In- System Programmable Flash
• Manufacturer: ATMEL Corporation

14.18.1
14.18.2
14.18.3
14.19 Analog Synchronization
7734M–AVR–03/10
Available Input Mode according to Running Mode
Event Capture
Using the Input Capture Unit
Some Input Modes are not consistent with some Running Modes. So the table below gives the input
modes which are valid according to running modes.
Table 14-6.
The PSCR can capture the value of time (PSCR counter) when a retrigger event or fault event occurs on
PSCR inputs. This value can be read by software in PICRrH/L register.
The main challenge when using the Input Capture unit is to assign enough processor capacity for handling
the incoming events. The time between two events is critical. If the processor has not read the captured
value in the PICR1 Register before the next event occurs, the PICR1 will be overwritten with a new value.
In this case the result of the capture will be incorrect.
When using the Input Capture interrupt, the PICR1 Register should be read as early in the interrupt han-
dler routine as possible. Even though the Input Capture interrupt has relatively high priority, the maximum
interrupt response time is dependent on the maximum number of clock cycles it takes to handle any of the
other interrupt requests.
PSCR generates a signal to synchronize the sample and hold; synchronization is mandatory for
measurements.
Input Mode Number :
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Available Input Modes according to Running Modes
1 Ramp Mode
Valid
Do not use
Do not use
Valid
Do not use
Do not use
Valid
Valid
Valid
Do not use
Valid
Do not use
2 Ramp Mode
Valid
Valid
Valid
Valid
Valid
Valid
Valid
Valid
Valid
Valid
AT90PWM81
4 Ramp Mode
Valid
Valid
Valid
Valid
Valid
Valid
Valid
Valid
Valid
Valid
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