ATMEGA644P-A15MZ Atmel, ATMEGA644P-A15MZ Datasheet - Page 273

• Manufacturer Part Number: ATMEGA644P-A15MZ
• Description: MCU AVR 64KB FLASH 16MHZ 44QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644P-A15MZ

• Package / Case: 44-VQFN Exposed Pad
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 32
• Eeprom Size: 2K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 4K x 8
• Program Memory Size: 64KB (64K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: I²C, SPI, UART/USART
• Core Size: 8-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7674F–AVR–09/09
The Boundary-scan logic is not included in the figures in the datasheet.
simple digital port pin as described in the section
details from
When no alternate port function is present, the Input Data - ID - corresponds to the PINxn Regis-
ter value (but ID has no synchronizer), Output Data corresponds to the PORT Register, Output
Control corresponds to the Data Direction - DD Register, and the Pull-up Enable - PUExn - cor-
responds to logic expression PUD · DDxn · PORTxn.
Digital alternate port functions are connected outside the dotted box in
scan chain read the actual pin value. For analog function, there is a direct connection from the
external pin to the analog circuit. There is no scan chain on the interface between the digital and
the analog circuitry, but some digital control signal to analog circuitry are turned off to avoid driv-
ing contention on the pads.
When JTAG IR contains EXTEST or SAMPLE_PRELOAD the clock is not sent out on the port
pins even if the CKOUT fuse is programmed. Even though the clock is output when the JTAG IR
contains SAMPLE_PRELOAD, the clock is not sampled by the boundary scan.
Figure 23-3. Boundary-scan Cell for Bi-directional Port Pin with Pull-up Function.
Pull-up Enable (PUE)
Output Control (OC)
Output Data (OD)
Input Data (ID)
Figure 23-3
replaces the dashed box in
0
1
From Last Cell
0
1
0
1
ShiftDR
ClockDR
D
D
FF1
FF0
To Next Cell
Q
Q
ATmega164P/324P/644P
“I/O-Ports” on page
UpdateDR
Figure
D
G
D
G
LD1
LD0
23-4.
Q
Q
0
1
0
1
0
1
EXTEST
Figure 23-4
71. The Boundary-scan
Figure 23-4
Vcc
to make the
shows a
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