ATMEGA8HVD-4MX Atmel, ATMEGA8HVD-4MX Datasheet - Page 73

• Manufacturer Part Number: ATMEGA8HVD-4MX
• Description: MCU AVR 8K FLASH 2.1-8V 4MHZ QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8HVD-4MX

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 5
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 2.4 V
• Data Converters: A/D 1x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 18-MLF® Exposed Pad (Staggered Leads), DFN
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Connectivity: -

15.5.2
8052B–AVR–09/08
GTCCR – General Timer/Counter Control Register
Table 15-1.
If external pin modes are used for the Timer/Counter n, transitions on the Tn pin will clock the
counter even if the pin is configured as an output. This feature allows software control of the
counting.
• Bit 7 – TSM: Timer/Counter Synchronization Mode
Writing the TSM bit to one activates the Timer/Counter Synchronization mode. In this mode,
the value that is written to the PSRSYNC bit is kept, hence keeping the corresponding pres-
caler reset signals asserted. This ensures that the corresponding Timer/Counters are halted
and can be configured to the same value without the risk of one of them advancing during con-
figuration. When the TSM bit is written to zero the PSRSYNC bit is cleared by hardware, and
the Timer/Counters start counting simultaneously.
• Bit 0 – PSRSYNC: Prescaler Reset
When this bit is one, Timer/Counter1 and Timer/Counter0 prescaler will be Reset. This bit is
normally cleared immediately by hardware, except if the TSM bit is set. Note that
Timer/Counter1 and Timer/Counter0 share the same prescaler and a reset of this prescaler
will affect both timers.
Bit
Read/Write
Initial Value
CSn2
0
0
0
0
1
1
1
1
CSn1
0
0
1
1
0
0
1
1
TSM
Clock Select Bit Description
R/W
7
0
CSn0
0
1
0
1
0
1
0
1
R
6
–
0
Description
No clock source (Timer/Counter stopped)
clk
clk
clk
clk
clk
External clock source on Tn pin. Clock on falling edge.
External clock source on Tn pin. Clock on rising edge.
I/O
I/O
I/O
I/O
I/O
R
5
–
0
/(No prescaling)
/8 (From prescaler)
/64 (From prescaler)
/256 (From prescaler)
/1024 (From prescaler)
R
4
–
0
R
3
–
0
ATmega4HVD/8HVD
R
2
–
0
R
1
–
0
PSRSYNC
R/W
0
0
GTCCR
73