Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD Data Sheet

Product codes
AT32UC3A3-XPLD
Page of 1021
561
32072H–AVR32–10/2012
AT32UC3A3
Figure 25-15. Typical Connection to a RS485 Bus 
If a timeguard has been configured the RTS pin will remain high for the duration specified in TG,
as shown in 
Figure 25-16. Example of RTS Drive with Timeguard Enabled
25.6.6
Hardware Handshaking
The USART features an out-of-band hardware handshaking flow control mechanism, imple-
mentable by connecting the RTS and CTS pins with the remote device, as shown in 
Figure 25-17. Connection with a Remote Device for Hardware Handshaking
USART
RTS
TXD
RXD
Differential 
Bus
D0
D1
D2
D3
D4
D5
D6
D7
TXD
Start 
Bit
Parity
Bit
Stop
Bit
Baud Rate
 Clock
TG = 4
Write
THR
TXRDY
TXEMPTY
RTS
USART
TXD
CTS
Remote 
Device
RXD
TXD
RXD
RTS
RTS
CTS