ATMEGA324P-A15MZ Atmel, ATMEGA324P-A15MZ Datasheet - Page 144

• Manufacturer Part Number: ATMEGA324P-A15MZ
• Description: MCU AVR 32KB FLASH 15MHZ 44-VQFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA324P-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: 1K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Program Memory Size: 32KB (32K 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

Frame Formats
144
ATmega32(L)
Figure 71. Synchronous Mode XCK Timing.
The UCPOL bit UCRSC selects which XCK clock edge is used for data sampling and which is
used for data change. As
ing XCK edge and sampled at falling XCK edge. If UCPOL is set, the data will be changed at
falling XCK edge and sampled at rising XCK edge.
A serial frame is defined to be one character of data bits with synchronization bits (start and stop
bits), and optionally a parity bit for error checking. The USART accepts all 30 combinations of
the following as valid frame formats:
•
•
•
•
A frame starts with the start bit followed by the least significant data bit. Then the next data bits,
up to a total of nine, are succeeding, ending with the most significant bit. If enabled, the parity bit
is inserted after the data bits, before the stop bits. When a complete frame is transmitted, it can
be directly followed by a new frame, or the communication line can be set to an idle (high) state.
Figure 72
optional.
Figure 72. Frame Formats
The frame format used by the USART is set by the UCSZ2:0, UPM1:0, and USBS bits in
UCSRB and UCSRC. The Receiver and Transmitter use the same setting. Note that changing
the setting of any of these bits will corrupt all ongoing communication for both the Receiver and
Transmitter.
St
(n)
P
Sp
IDLE
1 start bit
5, 6, 7, 8, or 9 data bits
no, even or odd parity bit
1 or 2 stop bits
(IDLE)
UCPOL = 1
UCPOL = 0
Start bit, always low.
Data bits (0 to 8).
Parity bit. Can be odd or even.
Stop bit, always high.
No transfers on the communication line (RxD or TxD). An IDLE line must be
high.
illustrates the possible combinations of the frame formats. Bits inside brackets are
St
RxD / TxD
RxD / TxD
0
XCK
XCK
Figure 71
1
2
shows, when UCPOL is zero the data will be changed at ris-
3
4
FRAME
[5]
[6]
[7]
[8]
Sample
Sample
[P]
Sp1 [Sp2] (St / IDLE)
2503N–AVR–06/08