AT90PWM1-16MU Atmel, AT90PWM1-16MU Datasheet - Page 174

• Manufacturer Part Number: AT90PWM1-16MU
• Description: IC AVR PWM 8KB FLASH 16MHZ 32QFN
• Manufacturer: Atmel
• Series: AVR® 90PWM Lightingr

Specifications of AT90PWM1-16MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 19
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 32-QFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

17.2.6
17.3
174
Data Modes
AT90PWM1
SPI Data Register – SPDR
• Bits 7:0 - SPD7:0: SPI Data
The SPI Data Register is a read/write register used for data transfer between the Register File
and the SPI Shift Register. Writing to the register initiates data transmission. Reading the regis-
ter causes the Shift Register Receive buffer to be read.
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
17-3
nal, ensuring sufficient time for data signals to stabilize. This is clearly seen by summarizing
Table 52
Table 55. CPOL Functionality
Figure 17-3. SPI Transfer Format with CPHA = 0
Bit
Read/Write
Initial Value
and
CPOL=0, CPHA=0
CPOL=0, CPHA=1
CPOL=1, CPHA=0
CPOL=1, CPHA=1
and
Figure
Table
SCK (CPOL = 0)
mode 0
SCK (CPOL = 1)
mode 2
SAMPLE I
MOSI/MISO
CHANGE 0
MOSI PIN
CHANGE 0
MISO PIN
SS
SPD7
MSB first (DORD = 0)
LSB first (DORD = 1)
R/W
17-4. Data bits are shifted out and latched in on opposite edges of the SCK sig-
X
7
53, as done below:
SPD6
R/W
6
X
MSB
LSB
Sample (Falling)
SPD5
Sample (Rising)
R/W
Leading Edge
Setup (Falling)
Setup (Rising)
5
X
Bit 6
Bit 1
SPD4
R/W
4
X
Bit 5
Bit 2
SPD3
R/W
3
X
Bit 4
Bit 3
Sample (Falling)
Sample (Rising)
Setup (Falling)
Setup (Rising)
Trailing eDge
SPD2
Bit 3
Bit 4
R/W
X
2
Bit 2
Bit 5
SPD1
R/W
X
1
Bit 1
Bit 6
SPD0
R/W
X
0
4378C–AVR–09/08
SPI Mode
LSB
MSB
Undefined
0
1
2
3
SPDR
Figure