ATmega16HVA Atmel Corporation, ATmega16HVA Datasheet - Page 91

• Manufacturer Part Number: ATmega16HVA
• Manufacturer: Atmel Corporation

Specifications of ATmega16HVA

• Flash (kbytes): 16 Kbytes
• Pin Count: 28
• Max. Operating Frequency: 4 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 3
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 6
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 6
• Adc Resolution (bits): 12
• Adc Speed (ksps): 1.9
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 256
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -20 to 85
• I/o Supply Class: 1.8 to 9.0
• Operating Voltage (vcc): 1.8 to 9.0
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 4
• Input Capture Channels: 2
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

17.10.2
17.10.3
17.10.4
8024A–AVR–04/08
TCNTnL – Timer/Counter n Register Low Byte
TCNTnH – Timer/Counter n Register High Byte
OCRnA – Timer/Counter n Output Compare Register A
The Timer/Counter Register TCNTnL gives direct access, both for read and write operations, to
the Timer/Counter unit 8-bit counter. Writing to the TCNTnL Register blocks (disables) the Com-
pare Match on the following timer clock. Modifying the counter (TCNTnL) while the counter is
running, introduces a risk of missing a Compare Match between TCNTnL and the OCRnx Regis-
ters. In 16-bit mode the TCNTnL register contains the lower part of the 16-bit Timer/Counter n
Register.
When 16-bit mode is selected (the TCWn bit is set to one) the Timer/Counter Register TCNTnH
combined to the Timer/Counter Register TCNTnL gives direct access, both for read and write
operations, to the Timer/Counter unit 16-bit counter. To ensure that both the high and low bytes
are read and written simultaneously when the CPU accesses these registers, the access is per-
formed using an 8-bit temporary high byte register (TEMP). This temporary register is shared by
all the other 16-bit registers. See
mode, this register is accessable for both reading and writing, but will not be updated by the
counter.
The Output Compare Register A contains an 8-bit value that is continuously compared with the
counter value (TCNTnL). A match can be used to generate an Output Compare interrupt.
In 16-bit mode the OCRnA register contains the low byte of the 16-bit Output Compare Register.
To ensure that both the high and the low bytes are written simultaneously when the CPU writes
to these registers, the access is performed using an 8-bit temporary high byte register (TEMP).
This temporary register is shared by all the other 16-bit registers. See
16-bit Mode” on page
Note that the OCRnA is not writable in Input Capture mode.
Bit
Read/Write
Initial Value
Bit
Read/Write
Initial Value
Bit
Read/Write
Initial Value
R/W
R/W
R/W
7
0
7
0
7
0
86.
R/W
R/W
R/W
6
0
6
0
6
0
R/W
R/W
R/W
5
0
”Accessing Registers in 16-bit Mode” on page
5
0
5
0
R/W
R/W
R/W
0
4
4
0
4
0
TCNTnL[7:0]
TCNTnH[7:0]
OCRnA[7:0]
R/W
R/W
R/W
3
0
3
0
3
0
ATmega8HVA/16HVA
R/W
R/W
R/W
2
0
2
0
2
0
R/W
R/W
R/W
”Accessing Registers in
1
0
1
0
1
0
R/W
R/W
R/W
0
0
0
0
0
0
86. In 8-bit
TCNTnH
TCNTnL
OCRnA
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