EFM32G200F64 Energy Micro, EFM32G200F64 Datasheet - Page 287

• Manufacturer Part Number: EFM32G200F64
• Description: MCU 32BIT 64KB FLASH 32-QFN
• Manufacturer: Energy Micro
• Series: Geckor

Specifications of EFM32G200F64

• Core Processor: ARM® Cortex-M3™
• Core Size: 32-Bit
• Speed: 32MHz
• Connectivity: EBI/EMI, I²C, IrDA, SmartCard, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 24
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.8 V
• Data Converters: A/D 4x12b, D/A 1x12b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-VQFN Exposed Pad
• Processor Series: EFM32G200
• Core: ARM Cortex-M3
• Data Bus Width: 32 bit
• Data Ram Size: 16 KB
• Interface Type: I2C, UART
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 2
• Operating Supply Voltage: 1.8 V to 3.8 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

21.3.3 Top Value
21.3.3.1 Buffered Top Value
21.3.3.2 Repeat Modes
21.3.3.2.1 Free Mode
2010-09-06 - d0001_Rev1.00
LETIMERn_CNT becomes equal to their value. When LETIMERn_CNT becomes equal to the value
of LETIMERn_COMP0, the interrupt flag COMP0 in LETIMERn_IF is set, and when LETIMERn_CNT
becomes equal to the value of LETIMERn_COMP1, the interrupt flag COMP1 in LETIMERn_IF is set.
If COMP0TOP in LETIMERn_CTRL is set, the value of LETIMERn_COMP0 acts as the top value of the
timer, and LETIMERn_COMP0 is loaded into LETIMERn_CNT on timer underflow. Else, the timer wraps
around to 0xFFFF. The underflow interrupt flag UF in LETIMERn_IF is set when the timer reaches zero.
If BUFTOP in LETIMERn_CTRL is set, the value of LETIMERn_COMP0 is buffered by
LETIMERn_COMP1. In this mode, the value of LETIMERn_COMP1 is loaded into LETIMERn_COMP0
every time LETIMERn_REP0 is about to decrement to 0. This can for instance be used in conjunction
with the buffered repeat mode to generate continually changing output waveforms.
Write operations to LETIMERn_COMP0 have priority over buffer loads.
By default, the timer wraps around to the top value or 0xFFFF on each underflow, and continues counting.
The repeat counters can be used to get more control of the operation of the timer, including defining
the number of times the counter should wrap around. Four different repeat modes are available, see
Table 21.1 (p. 287) .
Table 21.1. LETIMER Repeat Modes
The interrupt flags REP0 and REP1 in LETIMERn_IF are set whenever LETIMERn_REP0 or
LETIMERn_REP1 are decremented to 0 respectively. REP0 is also set when the value of
LETIMERn_REP1 is loaded into LETIMERn_REP0 in buffered mode.
In the free running mode, the LETIMER acts as a regular timer, and the repeat counter is disabled.
When started, the timer runs until it is stopped using the STOP command bit in LETIMERn_CMD. A
state machine for this mode is shown in Figure 21.2 (p. 288) .
REPMODE
00
01
10
11
Mode
Free
One-shot
Buffered
Double
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287
Description
The timer runs until it is stopped
The timer runs as long as
LETIMERn_REP0 != 0.
LETIMERn_REP0 is decremented at
each timer underflow.
The timer runs as long as
LETIMERn_REP0 != 0.
LETIMERn_REP0 is decremented
on each timer underflow. If
LETIMERn_REP1 has been written,
it is loaded into LETIMERn_REP0
when LETIMERn_REP0 is about to be
decremented to 0.
The timer runs as long as
LETIMERn_REP0 != 0 or
LETIMERn_REP1 != 0.
Both LETIMERn_REP0 and
LETIMERn_REP1 are decremented at
each timer underflow.
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