ATMEGA3250-16AUR Atmel, ATMEGA3250-16AUR Datasheet - Page 281

• Manufacturer Part Number: ATMEGA3250-16AUR
• Description: MCU AVR 32K FLASH 16MHZ 100TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA3250-16AUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• 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

26.7.2
2570M–AVR–04/11
Serial Programming Algorithm
Low: > 2 CPU clock cycles for f
High: > 2 CPU clock cycles for f
When writing serial data to the Atmel ATmega325/3250/645/6450, data is clocked on the rising
edge of SCK.
When reading data from the Atmel ATmega325/3250/645/6450, data is clocked on the falling
edge of SCK. See
To program and verify the Atmel ATmega325/3250/645/6450 in the serial programming mode,
the following sequence is recommended (See four byte instruction formats in
1. Power-up sequence:
2. Wait for at least 20ms and enable serial programming by sending the Programming
3. The serial programming instructions will not work if the communication is out of synchro-
4. The Flash is programmed one page at a time. The page size is found in
5. A: The EEPROM array is programmed one byte at a time by supplying the address and
6. Any memory location can be verified by using the Read instruction which returns the con-
7. At the end of the programming session, RESET can be set high to commence normal
Apply power between V
tems, the programmer can not guarantee that SCK is held low during power-up. In this
case, RESET must be given a positive pulse of at least two CPU clock cycles duration
after SCK has been set to “0”.
Enable serial instruction to pin MOSI.
nization. When in sync. the second byte (0x53), will echo back when issuing the third
byte of the Programming Enable instruction. Whether the echo is correct or not, all four
bytes of the instruction must be transmitted. If the 0x53 did not echo back, give RESET a
positive pulse and issue a new Programming Enable command.
page
address and data together with the Load Program Memory Page instruction. To ensure
correct loading of the page, the data low byte must be loaded before data high byte is
applied for a given address. The Program Memory Page is stored by loading the Write
Program Memory Page instruction with the 8 MSB of the address. If polling is not used,
the user must wait at least t
Accessing the serial programming interface before the Flash write operation completes
can result in incorrect programming.
data together with the appropriate Write instruction. An EEPROM memory location is first
automatically erased before new data is written. If polling (RDY/BSY) is not used, the
user must wait at least t
chip erased device, no 0xFFs in the data file(s) need to be programmed.
B: The EEPROM array is programmed one page at a time. The Memory page is loaded
one byte at a time by supplying the 2 LSB of the address and data together with the Load
EEPROM Memory Page instruction. The EEPROM Memory Page is stored by loading
the Write EEPROM Memory Page Instruction with the 4 MSB of the address. When using
EEPROM page access only byte locations loaded with the Load EEPROM Memory Page
instruction is altered. The remaining locations remain unchanged. If polling (RDY/BSY) is
not used, the used must wait at least t
26-11). In a chip erased device, no 0xFF in the data file(s) need to be programmed.
tent at the selected address at serial output MISO.
operation.
270. The memory page is loaded one byte at a time by supplying the 6/7 LSB of the
Figure 26-11
WD_EEPROM
CC
and GND while RESET and SCK are set to “0”. In some sys-
ck
ck
for timing details.
WD_FLASH
< 12 MHz, 3 CPU clock cycles for f
< 12 MHz, 3 CPU clock cycles for f
before issuing the next byte (See
WD_EEPROM
before issuing the next page. (See
ATmega325/3250/645/6450
before issuing the next page (See
ck
ck
>= 12 MHz
>= 12 MHz
Table
Table 26-10 on
Table
26-14.) In a
Table
26-15):
26-14.)
Table
281