AT91RM9200-CI-002 Atmel, AT91RM9200-CI-002 Datasheet - Page 380

• Manufacturer Part Number: AT91RM9200-CI-002
• Description: IC ARM9 MCU 256 BGA
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91RM9200-CI-002

• Core Processor: ARM9
• Core Size: 16/32-Bit
• Speed: 180MHz
• Connectivity: EBI/EMI, Ethernet, I²C, MMC, SPI, SSC, UART/USART, USB
• Peripherals: POR
• Number Of I /o: 122
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: ROM
• Ram Size: 48K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 256-BGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

28.5.3
Figure 28-7. SPI Transfer Format (NCPHA = 1, 8 bits per transfer)
380
SPCK cycle (for reference)
NSS (to slave)
(from master)
(from slave)
(CPOL = 0)
(CPOL = 1)
AT91RM9200
(Mode 1)
(Mode 3)
Data Transfer
SPCK
SPCK
MOSI
MISO
* Not defined, but normally MSB of previous character received.
Four modes are used for data transfers. These modes correspond to combinations of a pair of
parameters called clock polarity (CPOL) and clock phase (NCPHA) that determine the edges of
the clock signal on which the data are driven and sampled. Each of the two parameters has two
possible states, resulting in four possible combinations that are incompatible with one another.
Thus a master/slave pair must use the same parameter pair values to communicate. If multiple
slaves are used and fixed in different configurations, the master must reconfigure itself each
time it needs to communicate with a different slave.
Table 28-2
Table 28-2.
Figure 28-7
MSB
1
MSB
shows the four modes and corresponding parameter settings.
and
SPI Bus Protocol Mode
2
Figure 28-8
6
6
SPI Mode
0
1
2
3
3
5
5
show examples of data transfers.
4
4
4
5
3
3
6
6
2
2
CPOL
0
0
1
1
7
1
1
8
LSB
LSB
1768I–ATARM–09-Jul-09
NCPHA
1
0
1
0
*