AT90CAN128-16AE ATMEL Corporation, AT90CAN128-16AE Datasheet - Page 170

• Manufacturer Part Number: AT90CAN128-16AE
• Description: 8-bit Avr Microcontroller With 128K Bytes of Isp Flash And CAN Controller.flash (Kbytes) 128 Vcc (V) 2.7-5.5 EEPROM (Kbytes) 4 SRAM (bytes) 4K CAN (mess. Obj.) 15
• Manufacturer: ATMEL Corporation

Data Modes
170
AT90CAN128
There are four combinations of SCK phase and polarity with respect to serial data,
which are determined by control bits CPHA and CPOL. The SPI data transfer formats
are shown in Figure 78 and Figure 79. Data bits are shifted out and latched in on oppo-
site edges of the SCK signal, ensuring sufficient time for data signals to stabilize. This is
clearly seen by summarizing Table 72 and Table 73, as done below:
Table 75. CPOL Functionality
Figure 78. SPI Transfer Format with CPHA = 0
Figure 79. SPI Transfer Format with CPHA = 1
CPOL=0, CPHA=0
CPOL=0, CPHA=1
CPOL=1, CPHA=0
CPOL=1, CPHA=1
SCK (CPOL = 0)
mode 0
SCK (CPOL = 1)
mode 2
SAMPLE I
MOSI/MISO
CHANGE 0
MOSI PIN
CHANGE 0
MISO PIN
SCK (CPOL = 0)
mode 1
SCK (CPOL = 1)
mode 3
SAMPLE I
MOSI/MISO
CHANGE 0
MOSI PIN
CHANGE 0
MISO PIN
SS
SS
MSB first (DORD = 0)
LSB first (DORD = 1)
MSB first (DORD = 0)
LSB first (DORD = 1)
MSB
LSB
MSB
LSB
Sample (Falling)
Sample (Rising)
Bit 6
Bit 1
Leading Edge
Setup (Falling)
Setup (Rising)
Bit 6
Bit 1
Bit 5
Bit 2
Bit 5
Bit 2
Bit 4
Bit 3
Bit 4
Bit 3
Bit 3
Bit 4
Sample (Falling)
Sample (Rising)
Setup (Falling)
Trailing eDge
Setup (Rising)
Bit 3
Bit 4
Bit 2
Bit 5
Bit 2
Bit 5
Bit 1
Bit 6
Bit 1
Bit 6
4250C–CAN–03/04
LSB
MSB
SPI Mode
LSB
MSB
0
1
2
3