AT32UC3C2512C Automotive Atmel Corporation, AT32UC3C2512C Automotive Datasheet - Page 581

• Manufacturer Part Number: AT32UC3C2512C Automotive
• Manufacturer: Atmel Corporation

25.6.3.8
9166C–AVR-08/11
Parity
The USART supports five parity modes selected by programming the PAR field in the Mode
Register (MR). The PAR field also enables the Multidrop mode, see
582. Even and odd parity bit generation and error detection are supported.
If even parity is selected, the parity generator of the transmitter drives the parity bit at 0 if a num-
ber of 1s in the character data bit is even, and at 1 if the number of 1s is odd. Accordingly, the
receiver parity checker counts the number of received 1s and reports a parity error if the sam-
pled parity bit does not correspond. If odd parity is selected, the parity generator of the
transmitter drives the parity bit at 1 if a number of 1s in the character data bit is even, and at 0 if
the number of 1s is odd. Accordingly, the receiver parity checker counts the number of received
1s and reports a parity error if the sampled parity bit does not correspond. If the mark parity is
used, the parity generator of the transmitter drives the parity bit at 1 for all characters. The
receiver parity checker reports an error if the parity bit is sampled at 0. If the space parity is
used, the parity generator of the transmitter drives the parity bit at 0 for all characters. The
receiver parity checker reports an error if the parity bit is sampled at 1. If parity is disabled, the
transmitter does not generate any parity bit and the receiver does not report any parity error.
Table 25-7
depending on the configuration of the USART. Because there are two bits at 1, 1 bit is added
when a parity is odd, or 0 is added when a parity is even.
Table 25-7.
When the receiver detects a parity error, it sets the PARE (Parity Error) bit in the Channel Status
Register (CSR). The PARE bit can be cleared by writing the Control Register (CR) with the RST-
STA bit at 1.
Character
A
A
A
A
A
shows an example of the parity bit for the character 0x41 (character ASCII “A”)
Figure 25-21
Parity Bit Examples
Hexa
0x41
0x41
0x41
0x41
0x41
illustrates the parity bit status setting and clearing.
0100 0001
0100 0001
0100 0001
0100 0001
0100 0001
Binary
Parity Bit
None
1
0
1
0
”Multidrop Mode” on page
AT32UC3C
Parity Mode
Space
None
Even
Mark
Odd
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