ATTINY24-15SSZ Atmel, ATTINY24-15SSZ Datasheet - Page 93

• Manufacturer Part Number: ATTINY24-15SSZ
• Description: MCU AVR 2K FLASH 15MHZ 14-SOIC
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY24-15SSZ

• Package / Case: 14-SOIC (3.9mm Width), 14-SOL
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 12
• Eeprom Size: 128 x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 128 x 8
• Program Memory Size: 2KB (2K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: USI
• Core Size: 8-Bit
• Cpu Family: ATtiny
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 16MHz
• Interface Type: SPI/UART
• Total Internal Ram Size: 128Byte
• # I/os (max): 12
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 14
• Package Type: SOIC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

14.3
7701D–AVR–09/10
Accessing 16-bit Registers
TCNT1, OCR1A/B, and ICR1 are 16-bit registers that can be accessed by the Atmel
CPU via the 8-bit data bus. The 16-bit registers must be byte accessed using two read or write
operations. Each 16-bit timer has a single 8-bit register for temporary storage of the high byte
of the 16-bit access. The same temporary register is shared between all 16-bit registers within
each 16-bit timer. Accessing the low byte triggers the 16-bit read or write operation. When the
low byte of a 16-bit register is written by the CPU, the high byte stored in the temporary regis-
ter and the low byte written are both copied into the 16-bit register in the same clock cycle.
When the low byte of a 16-bit register is read by the CPU, the high byte of the 16-bit register is
copied into the temporary register in the same clock cycle as the low byte is read.
Not all 16-bit accesses use the temporary register for the high byte. Reading the OCR1A/B
16-bit registers does not involve using the temporary register.
To do a 16-bit write, the high byte must be written before the low byte. For a 16-bit read, the
low byte must be read before the high byte.
The following code examples show how to access the 16-bit timer registers, assuming that no
interrupts updates the temporary register. The same principle can be used directly for access-
ing the OCR1A/B and ICR1 registers. Note that when using C, the compiler handles the 16-bit
access.
Note:
The assembly code example returns the TCNT1 value in the r17:r16 register pair.
Assembly Code Examples
C Code Examples
...
; Set TCNT1 to 0x01FF
ldi r17,0x01
ldi r16,0xFF
out TCNT1H,r17
out TCNT1L,r16
; Read TCNT1 into r17:r16
in r16,TCNT1L
in r17,TCNT1H
...
unsigned int i;
...
/* Set TCNT1 to 0x01FF */
TCNT1 = 0x1FF;
/* Read TCNT1 into i */
i = TCNT1;
...
1. See
“About Code Examples” on page
(1)
Atmel ATtiny24/44/84 [Preliminary]
(1)
6.
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AVR
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