SAM3A8C Atmel Corporation, SAM3A8C Datasheet - Page 830

• Manufacturer Part Number: SAM3A8C
• Manufacturer: Atmel Corporation

35.7.9
35.7.9.1
35.7.9.2
830
830
SAM3X/A
SAM3X/A
Test Modes
Normal Mode
Automatic Echo Mode
Table 35-16. Receiver Time-out programming
The USART can be programmed to operate in three different test modes. The internal loopback
capability allows on-board diagnostics. In the loopback mode the USART interface pins are dis-
connected or not and reconfigured for loopback internally or externally.
Normal mode connects the RXD pin on the receiver input and the transmitter output on the TXD
pin.
Figure 35-55. Normal Mode Configuration
Automatic echo mode allows bit-by-bit retransmission. When a bit is received on the RXD pin, it
is sent to the TXD pin, as shown in
the TXD pin. The RXD pin is still connected to the receiver input, thus the receiver remains
active.
Figure 35-56. Automatic Echo Mode Configuration
LIN Specification
2.0
1.3
Transmitter
Transmitter
Receiver
Receiver
19 200 bit/s
20 000 bit/s
Baud Rate
1 000 bit/s
2 400 bit/s
9 600 bit/s
Figure
-
35-56. Programming the transmitter has no effect on
Time-out period
25 000 Tbits
4s
RXD
TXD
RXD
TXD
11057A–ATARM–17-Feb-12
11057A–ATARM–17-Feb-12
38 400
76 800
80 000
25 000
4 000
9 600
TO