ATMEGA645V-8AI Atmel, ATMEGA645V-8AI Datasheet - Page 187
![IC AVR MCU FLASH 64K 1.8V 64TQFP](/photos/12/13/121332/313-64-tqfp_sml.jpg)
ATMEGA645V-8AI
Manufacturer Part Number
ATMEGA645V-8AI
Description
IC AVR MCU FLASH 64K 1.8V 64TQFP
Manufacturer
Atmel
Series
AVR® ATmegar
Datasheet
1.ATMEGA325-16MU.pdf
(362 pages)
Specifications of ATMEGA645V-8AI
Core Processor
AVR
Core Size
8-Bit
Speed
8MHz
Connectivity
SPI, UART/USART, USI
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
53
Program Memory Size
64KB (32K x 16)
Program Memory Type
FLASH
Eeprom Size
2K x 8
Ram Size
4K x 8
Voltage - Supply (vcc/vdd)
1.8 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
64-TQFP, 64-VQFP
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
- Current page: 187 of 362
- Download datasheet (7Mb)
20.2.2
2570M–AVR–04/11
SPI Master Operation Example
Figure 20-3. Three-wire Mode, Timing Diagram
The Three-wire mode timing is shown in Figure 20-3. At the top of the figure is a USCK cycle ref-
erence. One bit is shifted into the USI Shift Register (USIDR) for each of these cycles. The
USCK timing is shown for both external clock modes. In External Clock mode 0 (USICS0 = 0), DI
is sampled at positive edges, and DO is changed (Data Register is shifted by one) at negative
edges. External Clock mode 1 (USICS0 = 1) uses the opposite edges versus mode 0, i.e., sam-
ples data at negative and changes the output at positive edges. The USI clock modes
corresponds to the SPI data mode 0 and 1.
Referring to the timing diagram (Figure 20-3.), a bus transfer involves the following steps:
1. The Slave device and Master device sets up its data output and, depending on the proto-
2. The Master generates a clock pulse by software toggling the USCK line twice (C and D).
3. Step 2. is repeated eight times for a complete register (byte) transfer.
4. After eight clock pulses (i.e., 16 clock edges) the counter will overflow and indicate that
The following code demonstrates how to use the USI module as a SPI Master:
col used, enables its output driver (mark A and B). The output is set up by writing the
data to be transmitted to the Serial Data Register. Enabling of the output is done by set-
ting the corresponding bit in the port Data Direction Register. Note that point A and B
does not have any specific order, but both must be at least one half USCK cycle before
point C where the data is sampled. This must be done to ensure that the data setup
requirement is satisfied. The 4-bit counter is reset to zero.
The bit value on the slave and master’s data input (DI) pin is sampled by the USI on the
first edge (C), and the data output is changed on the opposite edge (D). The 4-bit counter
will count both edges.
the transfer is completed. The data bytes transferred must now be processed before a
new transfer can be initiated. The overflow interrupt will wake up the processor if it is set
to Idle mode. Depending of the protocol used the slave device can now set its output to
high impedance.
SPITransfer:
SPITransfer_loop:
CYCLE
USCK
USCK
sts
ldi
sts
ldi
sts
lds
sbrs
DO
DI
( Reference )
A
USIDR,r16
r16,(1<<USIOIF)
USISR,r16
r16,(1<<USIWM0)|(1<<USICS1)|(1<<USICLK)|(1<<USITC)
USICR,r16
r16, USISR
r16, USIOIF
B
MSB
MSB
C
1
D
2
6
6
3
5
5
ATmega325/3250/645/6450
4
4
4
5
3
3
6
2
2
7
1
1
LSB
LSB
8
E
187
Related parts for ATMEGA645V-8AI
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![ATmega645](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
![ATMEGA645-16AU](/photos/12/13/121332/313-64-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU FLASH 64K 64TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA645-16AI](/photos/12/13/121332/313-64-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU FLASH 64K 5V 64TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA645-16MU](/photos/12/13/121326/313-64-qfn_tmb.jpg)
Part Number:
Description:
IC AVR MCU FLASH 64K 64-QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA645-16AUR](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
MCU AVR 64KB FLASH 16MHZ 64TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA645-16MUR](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
MCU AVR 64KB FLASH 16MHZ 64QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA645-16MI](/photos/12/13/121326/313-64-qfn_tmb.jpg)
Part Number:
Description:
IC AVR MCU FLASH 64K 5V 64QFN
Manufacturer:
Atmel
Datasheet:
![ATmega64](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
![ATMEGA64-16 AU](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
![ATMEGA64-16 AC](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
![ATMEGA64-16AU](/photos/12/13/121332/313-64-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA64-16MU](/photos/12/13/121326/313-64-qfn_tmb.jpg)
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64-QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA64-16AC](/photos/12/13/121332/313-64-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU 64K 16MHZ COM 64-TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA64-16AI](/photos/12/13/121332/313-64-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU 64K 16MHZ IND 64-TQFP
Manufacturer:
Atmel
Datasheet: