ST72F260G1M6 STMicroelectronics, ST72F260G1M6 Datasheet - Page 66

• Manufacturer Part Number: ST72F260G1M6
• Description: MCU 8BIT 4K FLASH ICP 28SOIC
• Manufacturer: STMicroelectronics
• Series: ST7r

Specifications of ST72F260G1M6

• Core Processor: ST7
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 4KB (4K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Data Converters: A/D 6x10b
• Processor Series: ST72F2x
• Core: ST7
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: I2C/SCI/SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 22
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Development Tools By Supplier: ST7F264-IND/USB, ST72F34X-SK/RAIS, ST7MDT10-DVP3, ST7MDT10-EMU3, STX-RLINK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 6-ch x 10-bit
• Controller Family/series: ST7
• No. Of I/o's: 22
• Ram Memory Size: 256Byte
• Cpu Speed: 8MHz
• No. Of Timers: 2
• Embedded Interface Type: I2C, SCI, SPI
• Rohs Compliant: Yes
• For Use With: 497-5046 - KIT TOOL FOR ST7/UPSD/STR7 MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-4840

ST72260Gx, ST72262Gx, ST72264Gx
16-BIT TIMER (Cont’d)
11.3.3.6 Pulse Width Modulation Mode
Pulse Width Modulation (PWM) mode enables the
generation of a signal with a frequency and pulse
length determined by the value of the OC1R and
OC2R registers.
Pulse Width Modulation mode uses the complete
Output Compare 1 function plus the OC2R regis-
ter, and so this functionality can not be used when
PWM mode is activated.
In PWM mode, double buffering is implemented on
the output compare registers. Any new values writ-
ten in the OC1R and OC2R registers are loaded in
their respective shadow registers (double buffer)
only at the end of the PWM period (OC2) to avoid
spikes on the PWM output pin (OCMP1). The
shadow registers contain the reference values for
comparison in PWM “double buffering” mode.
Note: There is a locking mechanism for transfer-
ring the OCiR value to the buffer. After a write to
the OCiHR register, transfer of the new compare
value to the buffer is inhibited until OCiLR is also
written.
Unlike in Output Compare mode, the compare
function is always enabled in PWM mode.
Procedure
To use pulse width modulation mode:
1. Load the OC2R register with the value corre-
2. Load the OC1R register with the value corre-
3. Select the following in the CR1 register:
4. Select the following in the CR2 register:
66/172
sponding to the period of the signal using the
formula in the opposite column.
sponding to the period of the pulse if (OLVL1=0
and OLVL2=1) using the formula in the oppo-
site column.
– Using the OLVL1 bit, select the level to be ap-
– Using the OLVL2 bit, select the level to be ap-
– Set OC1E bit: the OCMP1 pin is then dedicat-
– Set the PWM bit.
– Select the timer clock (CC[1:0]) (see
plied to the OCMP1 pin after a successful
comparison with OC1R register.
plied to the OCMP1 pin after a successful
comparison with OC2R register.
ed to the output compare 1 function.
Table 14
If OLVL1=1 and OLVL2=0 the length of the posi-
tive pulse is the difference between the OC2R and
OC1R registers.
If OLVL1=OLVL2 a continuous signal will be seen
on the OCMP1 pin.
The OC
ing application can be calculated using the follow-
ing formula:
Where:
t
f
PRESC
If the timer clock is an external clock the formula is:
Where:
t
f
The Output Compare 2 event causes the counter
to be initialized to FFFCh (See
Notes:
1. The OCF1 and OCF2 bits cannot be set by
2. The ICF1 bit is set by hardware when the coun-
CPU
EXT
hardware in PWM mode therefore the Output
Compare interrupt is inhibited.
ter reaches the OC2R value and can produce a
timer interrupt if the ICIE bit is set and the I bit is
cleared.
Clock Control
= Signal or pulse period (in seconds)
= CPU clock frequency (in hertz)
= Timer prescaler factor (2, 4 or 8 depend-
i
R register value required for a specific tim-
= Signal or pulse period (in seconds)
= External timer clock frequency (in hertz)
Counter
= OC1R
OCiR Value =
Counter
= OC2R
When
When
ing on CC[1:0] bits, see
Control
OCiR =
Bits)
Bits).
Pulse Width Modulation cycle
t
*
f
EXT
OCMP1 = OLVL2
PRESC
t
OCMP1 = OLVL1
Counter is reset
*
ICF1 bit is set
f
CPU
-5
to FFFCh
Figure
Table 14 Clock
- 5
45)