ZPSD511B1C15J STMicroelectronics, ZPSD511B1C15J Datasheet - Page 69

• Manufacturer Part Number: ZPSD511B1C15J
• Manufacturer: STMicroelectronics

Specifications of ZPSD511B1C15J

• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Supplier Unconfirmed

PSD5XX
Counter/Timer
Operation
(Cont.)
66
PSD5XX Family
Table 21. Registers Used By Counters
9.6.1 Counter/Timer Operation
There are four identical 16 bit Counter/Timers CNTR0,CNTR1,CNTR2 and CNTR3 and
associated Counter/Timer image registers IMG0,IMG1,IMG2 and IMG3. Refer to Table 21
for counter name and register correspondence. All Counter/Timers share a common clock
source. Each Counter/Timer can be operated in either WAVEFORM / PULSE mode or
EVENT COUNTER/TIME CAPTURE mode. Counter 2 can be set up as a Watchdog timer in
both modes. Note that in Event Counter/Time Capture mode COUNTER 2 can only be set
up as a Watch Dog Counter/Timer, whereas in the Waveform/Pulse mode Counter 2 can be
configured as a Pulse or Waveform generator or as a Watchdog timer. Refer to Table 24 for
possible combinations of Counter/Timer modes and refer to Figure 33 for additional details.
Each Counter/Timer can be controlled by an input pin or through a dedicated PPLD
macrocell output or by software. Counter/Timer outputs are available through port A or
port B pins in alternate function mode (Refer to the chapter on I/O ports). Polarity of
these inputs/outputs is software programmable. The following sections describe various
command and data registers that need to be initialized for proper function of these
Counter/Timers.
9.6.1.1 Counter/Timer Operating Modes
The PSD5XX Counter/Timer has five basic modes of operation: The Waveform and Pulse
or Event Counter, Time Capture, and Watchdog. The Waveform and Pulse modes cannot
be used in conjunction with Event and Time Capture modes. Both Waveform/Pulse or
Event Count/Time Capture modes can set Counter 2 into the fifth mode of operation, the
“WatchDog” mode.
The basic functional element used in all these modes is the Counter/Timer unit (CTU)
illustrated in Figure 33. This block consists of a 16 bit increment/decrement Counter, and a
16 bit image register with various control signals. The key function of the image register is
to enable microcontroller access of the Counter without asynchronously interrupting the
Counter. Software can configure each Counter/Timer using the associated Command
register. The Counter/Timer of the PSD5XX employs four CTUs to realize the various
modes of operation.
Counter Name
Counter 0
Counter 1
Counter 2
Counter 3
Counting Register
CNTR0
CNTR1
CNTR2
CNTR3
Image Register
IMG0
IMG1
IMG2
IMG3