EM351-RTR Ember, EM351-RTR Datasheet - Page 100

• Manufacturer Part Number: EM351-RTR
• Description: IC RF TXRX ZIGBEE 128KB 48QFN
• Manufacturer: Ember

Specifications of EM351-RTR

• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: 802.15.4 Zigbee
• Power - Output: 3dBm
• Sensitivity: -100dBm
• Voltage - Supply: 2.1 V ~ 3.6 V
• Current - Receiving: 26mA
• Current - Transmitting: 31mA
• Data Interface: PCB, Surface Mount
• Memory Size: 128kB Flash, 12kB RAM
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-QFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Applications: -
• Other names: 636-1010-2

The GPIO pins assigned to these signals are shown in Table 8-10.
1
8.6.2
The UART baud rate clock is produced by a programmable baud generator starting from the 24 Hz clock:
The integer portion of the divisor, N, is written to the SC1_UARTPER register and the fractional part, F, to the
SC1_UARTFRAC register. Table 8-11 shows the values used to generate some common baud rates and their
associated clock frequency error. The UART requires an internal clock that is at least eight times the baud
rate clock, so the minimum allowable setting for SC1_UARTPER is 8.
The UART can miss bytes when the inter-byte gap is long or there is a baud rate mismatch between receiver
and transmitter. The UART may detect a parity and/or framing error on the corrupted byte, but there will not
necessarily be any error detected.
Direction
GPIO Configuration
SC1 pin
only used if RTS/CTS hardware flow control is enabled.
Baud Rate
(bits/sec)
Set Up and Configuration
115200
230400
460800
921600
19200
38400
57600
2400
4800
9600
300
Table 8-11. UART Baud Rate Divisors for Common Baud Rates
Output (push-pull)
baud
Alternate
Output
TXD
SC1_UARTPER
PB1
=
24
2
N
40000
5000
2500
1250
Table 8-10. UART GPIO Usage
MHz
625
312
208
104
52
26
13
+
Final
8-25
F
RXD
Input
Input
PB2
SC1_UARTFRAC
0
0
0
0
0
1
1
0
0
0
0
nCTS
Input
Input
PB3
EM351 / EM357
1
Baud Rate Error (%)
Output (push-pull)
+ 0.16
+ 0.16
+ 0.16
+ 0.16
- 0.08
Alternate
120-035X-000G
0
0
0
0
0
0
nRTS
Output
PB4
1