ATMEGA324P-A15MZ Atmel, ATMEGA324P-A15MZ Datasheet - Page 91

• 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

Reusing the
Temporary High Byte
Register
Timer/Counter
Clock Sources
Counter Unit
2503N–AVR–06/08
The following code examples show how to do an atomic write of the TCNT1 Register contents.
Writing any of the OCR1A/B or ICR1 Registers can be done by using the same principle.
Note:
The assembly code example requires that the r17:r16 register pair contains the value to be writ-
ten to TCNT1.
If writing to more than one 16-bit register where the high byte is the same for all registers written,
then the high byte only needs to be written once. However, note that the same rule of atomic
operation described previously also applies in this case.
The Timer/Counter can be clocked by an internal or an external clock source. The clock source
is selected by the Clock Select logic which is controlled by the Clock Select (CS12:0) bits
located in the Timer/Counter Control Register B (TCCR1B). For details on clock sources and
prescaler, see
The main part of the 16-bit Timer/Counter is the programmable 16-bit bi-directional counter unit.
Figure 41
Assembly Code Example
C Code Example
TIM16_WriteTCNT1:
void TIM16_WriteTCNT1 ( unsigned int i )
{
}
; Save global interrupt flag
in
; Disable interrupts
cli
; Set TCNT1 to r17:r16
out TCNT1H,r17
out TCNT1L,r16
; Restore global interrupt flag
out SREG,r18
ret
unsigned char sreg;
unsigned int i;
/* Save global interrupt flag */
sreg = SREG;
/* Disable interrupts */
_CLI();
/* Set TCNT1 to i */
TCNT1 = i;
/* Restore global interrupt flag */
SREG = sreg;
1. See
shows a block diagram of the counter and its surroundings.
r18,SREG
“Timer/Counter0 and Timer/Counter1 Prescalers” on page
“About Code Examples” on page
(1)
(1)
7.
ATmega32(L)
84.
91