User's Manual

TOBY-R2 series - System Integration Manual
UBX-16010572 - R04 System description
Page 38 of 147
Flow control handshakes are supported by the UART interface and can be set by appropriate AT commands (see
u-blox AT Commands Manual [2], &K, +IFC, \Q AT commands): hardware flow control (over the RTS / CTS lines),
software flow control (XON/XOFF), or none flow control.
Hardware flow control is enabled by default.
The one-shot autobauding is supported: the automatic baud rate detection is performed only once, at module
start up. After the detection, the module works at the detected baud rate and the baud rate can only be
changed by AT command (see u-blox AT Commands Manual [3], +IPR).
One-shot automatic baud rate recognition (autobauding) is enabled by default.
The following baud rates can be configured by AT command (see u-blox AT Commands Manual [2], +IPR):
 9600 b/s
 19200 b/s
 38400 b/s
 57600 b/s
 115200 b/s, default value when one-shot autobauding is disabled
 230400 b/s
 460800 b/s
 921600 b/s
 3000000 b/s
 3250000 b/s
 6000000 b/s
 6500000 b/s
Baud rates higher than 460800 b/s cannot be automatically detected by TOBY-R2 series modules.
The modules support the one-shot automatic frame recognition in conjunction with the one-shot autobauding.
The following frame formats can be configured by AT command (see u-blox AT Commands Manual [2], +ICF):
 8N1 (8 data bits, No parity, 1 stop bit), default frame configuration with fixed baud rate, see Figure 18
 8E1 (8 data bits, even parity, 1 stop bit)
 8O1 (8 data bits, odd parity, 1 stop bit)
 8N2 (8 data bits, No parity, 2 stop bits)
 7E1 (7 data bits, even parity, 1 stop bit)
 7O1 (7 data bits, odd parity, 1 stop bit)
D0 D1 D2 D3 D4 D5 D6 D7
Start of 1-Byte
transfer
Start Bit
(Always 0)
Possible Start of
next transfer
Stop Bit
(Always 1)
t
bit
= 1/(Baudrate)
Normal Transfer, 8N1
Figure 18: Description of UART 8N1 frame format (8 data bits, no parity, 1 stop bit)