ATMEGA3250P-20AUR Atmel, ATMEGA3250P-20AUR Datasheet - Page 274

• Manufacturer Part Number: ATMEGA3250P-20AUR
• Description: MCU AVR 32K FLASH 20MHZ 100TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA3250P-20AUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 69
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

25.2.1
25.3
25.4
25.5
25.5.1
274
Signature Bytes
Calibration Byte
Parallel Programming Parameters, Pin Mapping, and Commands
ATmega325P/3250P
Latching of Fuses
Signal Names
The fuse values are latched when the device enters programming mode and changes of the
fuse values will have no effect until the part leaves Programming mode. This does not apply to
the EESAVE Fuse which will take effect once it is programmed. The fuses are also latched on
Power-up in Normal mode.
All Atmel microcontrollers have a three-byte signature code which identifies the device. This
code can be read in both serial and parallel mode, also when the device is locked. The three
bytes reside in a separate address space. For the ATmega325P/3250P the signature bytes are
given in
Table 25-6.
The ATmega325P/3250P has a byte calibration value for the internal RC Oscillator. This byte
resides in the high byte of address 0x000 in the signature address space. During reset, this byte
is automatically written into the OSCCAL Register to ensure correct frequency of the calibrated
RC Oscillator.
This section describes how to parallel program and verify Flash Program memory, EEPROM
Data memory, Memory Lock bits, and Fuse bits in the ATmega325P/3250P. Pulses are
assumed to be at least 250ns unless otherwise noted.
In this section, some pins of the ATmega325P/3250P are referenced by signal names describ-
ing their functionality during parallel programming, see
on page
The XA1/XA0 pins determine the action executed when the XTAL1 pin is given a positive pulse.
The bit coding is shown in
When pulsing WR or OE, the command loaded determines the action executed. The different
Commands are shown in
Parts
ATmega325P
ATmega3250P
Table 25-6
275. Pins not described in the following table are referenced by pin names.
Device and JTAG ID
0x000
0x1E
0x1E
Table 25-10 on page
Signature Bytes Address
Table 25-9 on page
0x001
0x95
0x95
0x002
0x0D
0x0E
276.
276.
Figure 25-1 on page 275
Part Number
950D
950E
JTAG
Manufacture ID
and
8023F–AVR–07/09
0x1F
0x1F
Table 25-7