Data Sheet

459
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181G–SAM-D21_Datasheet–09/2015
z Bits 19:18 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to
zero when this register is written. These bits will always return zero when read.
z Bit 17:16 – TXPO[1:0]: Transmit Data Pinout
These bits define the transmit data (TxD) and XCK pin configurations.
This bit is not synchronized.
Table 25-9. Transmit Data Pinout
z Bits 15:13 – SAMPR[2:0]: Sample Rate
These bits define the sample rate.
These bits are not synchronized.
Table 25-10. Sample Rate
z Bits 12:9 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to
zero when this register is written. These bits will always return zero when read.
z Bit 8 – IBON: Immediate Buffer Overflow Notification
This bit controls when the buffer overflow status bit (STATUS.BUFOVF) is asserted when a buffer overflow occurs.
Table 25-8. Receive Data Pinout
RXPO[1:0] Name Description
0x0 PAD[0] SERCOM PAD[0] is used for data reception
0x1 PAD[1] SERCOM PAD[1] is used for data reception
0x2 PAD[2] SERCOM PAD[2] is used for data reception
0x3 PAD[3] SERCOM PAD[3] is used for data reception
TXPO
TxD Pin
Location
XCK Pin Location
(When Applicable)
RTS CTS
0x0 SERCOM PAD[0] SERCOM PAD[1] N/A N/A
0x1 SERCOM PAD[2] SERCOM PAD[3] N/A N/A
0x2 SERCOM PAD[0] N/A SERCOM PAD[2] SERCOM PAD[3]
0x3 Reserved
SAMPR[2:0] Description
0x0 16x over-sampling using arithmetic baud rate generation.
0x1 16x over-sampling using fractional baud rate generation.
0x2 8x over-sampling using arithmetic baud rate generation.
0x3 8x over-sampling using fractional baud rate generation.
0x4 3x over-sampling using arithmetic baud rate generation.
0x5-0x7 Reserved