EFM32G200F16 Energy Micro, EFM32G200F16 Datasheet - Page 194

• 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

16.3.4 PRS-triggered Transmissions
16.3.5 DMA Support
16.3.6 Transmission Delay
16.3.7 Interrupts
2010-09-06 - d0001_Rev1.00
If a transmission must be started on an event with very little delay, the PRS system can be used
to trigger the transmission. The PRS channel to use as a trigger can be selected using TSEL in
USARTn_TRIGCTRL. When a positive edge is detected on this signal, the receiver is enabled if RXTEN
in USARTn_TRIGCTRL is set, and the transmitter is enabled if TXTEN in USARTn_TRIGCTRL is set.
Only one signal input is supported by the USART.
The USART has full DMA support. The DMA controller can write to the transmit buffer using the
registers USARTn_TXDATA, USARTn_TXDATAX, USARTn_TXDOUBLE and USARTn_TXDOUBLEX,
and it can read from the receive buffer using the registers USARTn_RXDATA, USARTn_RXDATAX,
USARTn_RXDOUBLE and USARTn_RXDOUBLEX. This enables single byte transfers, 9 bit data +
control/status bits, double byte and double byte + control/status transfers both to and from the USART.
A request for the DMA controller to read from the USART receive buffer can come from the following
source:
• Data available in the receive buffer
• Data available in the receive buffer and data is for the RIGHT I2S channel. Only used in I2S mode.
A write request can come from one of the following sources:
• Transmit buffer and shift register empty. No data to send.
• Transmit buffer has room for more data
• Transmit buffer has room for RIGHT I2S data. Only used in I2S mode
Even though there are two sources for write requests to the DMA, only one should be used at a time,
since the requests from both sources are cleared even though only one of the requests are used.
In some cases, it may be sensible to temporarily stop DMA access to the USART when an error such
as a framing error has occurred. This is enabled by setting ERRSDMA in USARTn_CTRL.
By configuring TXDELAY in USARTn_CTRL, the transmitter can be forced to wait a number of bit-
periods from it is ready to transmit data, to it actually transmits the data. This delay is only applied to the
first frame transmitted after the transmitter has been idle. When transmitting frames back-to-back the
delay is not introduced between the transmitted frames.
This is useful on half duplex buses, because the receiver always returns received frames to software
during the first stop-bit. The bus may still be driven for up to 3 baud periods, depending on the current
frame format. Using the transmission delay, a transmission can be started when a frame is received,
and it is possible to make sure that the transmitter does not begin driving the output before the frame
on the bus is completely transmitted.
TXDELAY in USARTn_CTRL only applies to asynchronous transmission.
The interrupts generated by the USART are combined into two interrupt vectors. Interrupts related to
reception are assigned to one interrupt vector, and interrupts related to transmission are assigned to
When operating as SPI slave in half duplex mode, TX has to be tristated (not disabled)
during data reception if the slave is to transmit data in the current transfer.
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