AT91SAM7S32-AI ATMEL [ATMEL Corporation], AT91SAM7S32-AI Datasheet - Page 240

• Manufacturer Part Number: AT91SAM7S32-AI
• Description: AT91 ARM Thumb-based Microcontrollers
• Manufacturer: ATMEL [ATMEL Corporation]

SPI Transmit Data Register
Name:
Access Type:
• 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:
If PCSDEC = 1:
• LASTXFER: Last Transfer
0 = No effect.
1 = The current NPCS will be deasserted after the character written in TD has been transferred. When CSAAT is set, this
allows to close the communication with the current serial peripheral by raising the corresponding NPCS line as soon as TD
transfer has completed.
240
PCS = xxx0
PCS = xx01
PCS = x011
PCS = 0111
PCS = 1111
(x = don’t care)
NPCS[3:0] output signals = PCS
31
23
15
–
–
7
AT91SAM7S32 Preliminary
SPI_TDR
Write-only
NPCS[3:0] = 1110
NPCS[3:0] = 1101
NPCS[3:0] = 1011
NPCS[3:0] = 0111
forbidden (no peripheral is selected)
30
22
14
–
–
6
29
21
13
–
–
5
28
20
12
–
–
4
TD
TD
27
19
11
–
3
26
18
10
–
2
PCS
25
17
–
1
9
6071A–ATARM–28-Oct-04
LASTXFER
24
16
8
0