EFM32G200F16 Energy Micro, EFM32G200F16 Datasheet - Page 294

• Manufacturer Part Number: EFM32G200F16
• Description: MCU 32BIT 16KB FLASH 32-QFN
• Manufacturer: Energy Micro
• Series: Geckor

Specifications of EFM32G200F16

• 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: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K 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: 8 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

21.3.5 Examples
21.3.5.1 Triggered Output Generation
2010-09-06 - d0001_Rev1.00
This section presents a couple of usage examples for the LETIMER.
Example 21.1. LETIMER Triggered Output Generation
If both LETIMERn_CNT and LETIMERn_REP0 are 0 in buffered mode, and COMP0TOP and BUFTOP
in LETIMERn_CTRL are set, the values of LETIMERn_COMP1 and LETIMERn_REP1 are loaded into
LETIMERn_CNT and LETIMERn_REP0 respectively when the timer is started. If no additional writes to
LETIMERn_REP1 are done before the timer stops, LETIMERn_REP1 determines the number of pulses/
toggles generated on the output, and LETIMERn_COMP1 determines the period lengths.
As the RTC can be used to start the LETIMER, the RTC and LETIMER can thus be combined to generate
specific pulse-trains at given intervals. Software can update LETIMERn_COMP1 and LETIMERn_REP1
to change the number of pulses and pulse-period in each train, but if changes are not required, software
does not have to update the registers between each pulse train.
For the example in Figure 21.9 (p. 294) , the initial values cause the LETIMER to generate two pulses
with 3 cycle periods, or a single pulse 3 cycles wide every time the LETIMER is started. After the output
has been generated, the LETIMER stops, and is ready to be triggered again.
Figure 21.9. LETIMER Triggered Operation
LFACLK
UFOA0 = 01
UFOA0 = 10
Int. flags set
LETn_O0
LETn_O1
LETIMERn
TOP1
TOP0
REP0
REP1
Initial configuration,
CNT
REP1 just written
X
2
0
0
2
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2
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2
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UFIF
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REP0IF
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UFIF
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1
Stop
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START= 1
u
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Write
2
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0
0
294
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UFIF
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REP0IF
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UFIF
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1
Stop
u
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START= 1
u
Write
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0
0
u
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2
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UFIF
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