Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet

Product codes

ATSAM4S-WPIR-RD

685

SAM4S Series [DATASHEET]

Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14

33.8.4 SPI Transmit Data Register

Name:

SPI_TDR

Address:

0x4000800C

Access:

Write-only



TD: Transmit Data

Data to be transmitted by the SPI Interface is stored in this register. Information to be transmitted must be written to the

transmit data register in a right-justified format.



PCS: Peripheral Chip Select

This field is only used if variable peripheral select is active (PS = 1).
If PCSDEC = 0:

PCS = xxx0

NPCS[3:0] = 1110

PCS = xx01

NPCS[3:0] = 1101

PCS = x011

NPCS[3:0] = 1011

PCS = 0111

NPCS[3:0] = 0111

PCS = 1111

forbidden (no peripheral is selected)

(x = don’t care)

If PCSDEC = 1:

NPCS[3:0] output signals = PCS.



LASTXFER: Last Transfer

0: No effect.
1: The current NPCS is de-asserted after the transfer of the character written in TD. When CSAAT is set, the communica-

tion with the current serial peripheral can be closed by raising the corresponding NPCS line as soon as TD transfer is

completed.
This field is only used if variable peripheral select is active (PS = 1).

–

LASTXFER

–

PCS