ST7FLITE39F2U6 STMicroelectronics, ST7FLITE39F2U6 Datasheet - Page 43

• Manufacturer Part Number: ST7FLITE39F2U6
• Description: IC MCU 8BIT 8K FLASH 20QFN
• Manufacturer: STMicroelectronics
• Series: ST7r

Specifications of ST7FLITE39F2U6

• Core Processor: ST7
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: LINSCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 15
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 384 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 7x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-QFN
• For Use With: 497-8406 - BOARD STF20NM50FD/STF7LITE39BF2497-8403 - BOARD DEMO STCC08 AC SW DETECTOR497-6398 - BOARD EVAL ST7FLITE39/STM1403497-5858 - EVAL BOARD PLAYBACK ST7FLITE497-5514 - EVAL BOARD THERMO CONTROL REFRIG497-5049 - KIT STARTER RAISONANCE ST7FLITE
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-5635

POWER SAVING MODES (Cont’d)
Figure 26. ACTIVE-HALT Timing Overview
Figure 27. ACTIVE-HALT Mode Flow-chart
Notes:
1. This delay occurs only if the MCU exits ACTIVE-
HALT mode by means of a RESET.
2. Peripherals clocked with an external clock
source can still be active.
3. Only the RTC1 interrupt and some specific inter-
rupts can exit the MCU from ACTIVE-HALT mode.
Refer to Table 6, “Interrupt Mapping,” on page 36
for more details.
4. Before servicing an interrupt, the CC register is
pushed on the stack. The I bit of the CC register is
set during the interrupt routine and cleared when
the CC register is popped.
[Active Halt Enabled]
INSTRUCTION
(AWUCSR.AWUEN=0)
HALT INSTRUCTION
RUN
(Active Halt enabled)
N
HALT
INTERRUPT
ACTIVE
HALT
Y
256 OR 4096 CPU
CYCLE DELAY
INTERRUPT
3)
RESET
OR SERVICE INTERRUPT
FETCH RESET VECTOR
CLOCK CYCLE
OR
OSCILLATOR
PERIPHERALS
OSCILLATOR
PERIPHERALS
OSCILLATOR
PERIPHERALS
CPU
I BIT
CPU
I BIT
CPU
I BIT
N
256 OR 4096 CPU
RESET
Y
1)
VECTOR
FETCH
RUN
2)
2)
DELAY
OFF
OFF
OFF
ON
ON
ON
X
ON
ON
ON
X
0
4)
4)
9.6 AUTO WAKE UP FROM HALT MODE
Auto Wake Up From Halt (AWUFH) mode is simi-
lar to Halt mode with the additional of an internal
RC oscillator for wake-up. Compared to ACTIVE-
HALT mode, AWUFH has lower power consump-
tion (the main clock is not kept running), but there
is no accurate realtime clock available.
It is entered by executing the HALT instruction
when the AWUEN bit in the AWUCSR register has
been set.
Figure 28. AWUFH Mode Block Diagram
As soon as HALT mode is entered, and if the
AWUEN bit has been set in the AWUCSR register,
the AWU RC oscillator provides a clock signal
(f
er and a programmable prescaler controlled by the
AWUPR register. The output of this prescaler pro-
vides the delay time. When the delay has elapsed
the AWUF flag is set by hardware and an interrupt
wakes-up the MCU from Halt mode. At the same
time the main oscillator is immediately turned on
and a 256 cycle delay is used to stabilize it. After
this start-up delay, the CPU resumes operation by
servicing the AWUFH interrupt. The AWU flag and
its associated interrupt are cleared by software
reading the AWUCSR register.
To compensate for any frequency dispersion of
the AWU RC oscillator, it can be calibrated by
measuring the clock frequency f
calculating the right prescaler value. Measurement
mode is enabled by setting the AWUM bit in the
AWUCSR register in Run mode. This connects
f
lad timer, allowing the f
using the main oscillator clock as a reference time-
base.
AWU_RC
AWU RC
32-KHz
AWU_RC
Oscillator
Oscillator
f
AWU_RC
divider
/64
to the input capture of the 12-bit Auto-Re-
). Its frequency is divided by a fixed divid-
AWUCK Opt bit
1
0
prescaler/1 .. 255
AWUFH
AWU_RC
Auto-Reload
Input Capture
to
AWU_RC
to be measured
ST7LITE3xF2
(ei0 source)
AWUFH
interrupt
and then
43/173
Timer
1