ST52F513G3M6 STMicroelectronics, ST52F513G3M6 Datasheet - Page 73

• Manufacturer Part Number: ST52F513G3M6
• Manufacturer: STMicroelectronics

Specifications of ST52F513G3M6

• Cpu Family: ST52
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: I2C/SCI/SPI
• Program Memory Type: Flash
• Program Memory Size: 8KB
• Total Internal Ram Size: 256Byte
• # I/os (max): 22
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 28
• Package Type: SO
• Lead Free Status / Rohs Status: Compliant

12 PWM/TIMERS
12.1 Introduction
ST52F510/513 offers two on-chip PWM/Timer
peripherals. All ST52F510/513 PWM/Timers have
the same internal structure. The timer consists of a
16-bit counter with a 16-bit programmable
Prescaler, giving a maximum count of 2
Figure
Each timer has two different working modes, which
can be selected by setting the correspondent bit
TxMOD of the PWMx_CR1 Conf. Register: Timer
Mode and PWM (Pulse Width Modulation) Mode.
All the Timers have Autoreload Functions; in PWM
Mode the reload value can be set by the user.
Each timer output is available on the apposite
external pins configured in Alternate Function and
in one of the Output modes.
PWM/Timer 0 can also use external START/STOP
signals in order to perform Input capture and
Output compare, external RESET signal, and
external CLOCK to count external events: TSTRT,
TRES and TCLK pins. In addition, the START/
STOP and RESET signals have configurable
polarity (falling or rising edge).
Remark: To use TRES, TSTRT, TCLK external
signals the related pins must be configured in
Alternate Function and in one of Input modes.
For each timer, the contents of the 16-bit counter
are incremented on the Rising Edge of the 16-bit
prescaler output (PRESCOUT) and they can be
read at any instant of the counting phase by
accessing
PWMx_COUNT_IN_x; the value is stored in two 8-
bit registers (MSB and LSB) for each PWM/Timer.
The Input Registers couple PWMx_CAPTURE_x
store the counter value after the last Stop signal
(only Timer Mode). The counter value is not stored
after a Reset Signal.
Figure 12.1 PWM/Timer Counter block diagram
12.1).
TMRCLKx
the
BIT 0
BIT 0
Input
BIT 1
BIT 1
BIT 2
BIT 2
Registers
BIT 3
BIT 3
32
16-BIT COUNTER
16-BIT PRESCALER
17 - 1 MULTIPLEXER
(see
BIT 4
BIT 4
PRESCOUT
BIT 5
BIT 5
Warning: Both of the PWMx_COUNT_IN_x
registers must be always read. To avoid side
effects, the values stored inside these registers are
frozen, and new updates cannot be stored, until
both the values are read.
The peripheral status can also be read from the
Input Registers PWMx_STATUS. These registers
report START/STOP, SET/RESET status, TxOUT
signal and the counter overflow flag. This last
signal is set after the first EOC and it is reset by a
Timer RESET (internal or external).
12.2 Timer Mode
Timer Mode is selected writing 0 in the TxMOD bit.
Each Timer requires three signals: Timer Clock
(TMRCLKx), Timer Reset (TxRES) and Timer Start
(TxSTRT) (see
can be generated internally, and/or externally only
for Timer 0, by using TRES, TSTRT and TCLK
pins.
The Prescaler output (PRESCOUT) increments
the Counter value on the rising edge. PRESCOUT
is obtained from the internal clock signal (CLKM)
or, only for TIMER0, from the external signal
provided on the apposite pin.
Note: The external clock signal applied on the
TCLK pin must have a frequency that is at least two
times smaller than the internal master clock.
The prescaler output period can be selected by
setting the TxPRESC bits with one of the 17
division factors available. TMRCLK frequency is
divided by a factor equal to the power of two of the
prescaler values (up to 2
TxRES resets the content of the 16-bit counter to
zero. It is generated by writing 0 in the TxRES bit
of the PWMx_CR1 Configuration Register and/or it
can be driven by the TRES pin if configured (only
Timer0).
BIT 14
BIT 14
Figure
BIT 15
BIT 15
12.1). Each of these signals
ST52510xx ST52513xx
16
).
PRESCx
TxRES
TxSTRT
73/136