EFM32G200F16 Energy Micro, EFM32G200F16 Datasheet - Page 190

• 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

2010-09-06 - d0001_Rev1.00
USARTn_CTRL or through an external connection. The TX output should be configured as open-drain
in the GPIO module.
When no parity error is identified by the receiver, the data frame is as shown in Figure 16.12 (p. 190)
. The frame consists of 8 data bits, a parity bit, and 2 stop bits. The transmitter does not drive the output
line during the guard time.
Figure 16.12. USART ISO 7816 Data Frame Without Error
If a parity error is detected by the receiver, it pulls the line I/O line low after half a stop bit, see
Figure 16.13 (p. 190) . It holds the line low for one bit-period before it releases the line. In this case,
the guard time is extended by one bit period before a new transmission can start, resulting in a total
of 3 stop bits.
Figure 16.13. USART ISO 7816 Data Frame With Error
On a parity error, the NAK is generated by hardware. The NAK generated by the receiver is sampled
as the stop-bit of the frame. Because of this, parity errors when in SmartCard mode are reported with
both a parity error and a framing error.
When transmitting a T0 frame, the USART receiver on the transmitting side samples position 16, 17 and
18 in the stop-bit to detect the error signal when in 16x oversampling mode as shown in Figure 16.14 (p.
191) . Sampling at this location places the stop-bit sample in the middle of the bit-period used for the
error signal (NAK).
If a NAK is transmitted by the receiver, it will thus appear as a framing error at the transmitter, and the
FERR interrupt flag in USARTn_IF will be set. If SCRETRANS USARTn_CTRL is set, the transmitter
will automatically retransmit a NACK’ed frame. The transmitter will retransmit the frame until it is ACK’ed
by the receiver. This only works when the number of databits in a frame is configured to 8.
Set SKIPPERRF in USARTn_CTRL to make the receiver discard frames with parity errors. The PERR
interrupt flag in USARTn_IF is set when a frame is discarded because of a parity error.
Stop or idle
Stop or idle
S
S
0
0
1
1
2
2
ISO 7816 Fram e without error
3
3
ISO 7816 Fram e with error
4
...the world's most energy friendly microcontrollers
4
190
5
5
6
6
7
7
P
P
Stop
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NAK
Stop
Stop
Start or idle
Start or idle