ATMEGA128RFA1-ZU Atmel, ATMEGA128RFA1-ZU Datasheet - Page 306

• Manufacturer Part Number: ATMEGA128RFA1-ZU
• Description: IC AVR MCU 2.4GHZ XCEIVER 64QFN
• Manufacturer: Atmel
• Series: ATMEGAr

Specifications of ATMEGA128RFA1-ZU

• Frequency: 2.4GHz
• Data Rate - Maximum: 2Mbps
• Modulation Or Protocol: 802.15.4 Zigbee
• Applications: General Purpose
• Power - Output: 3.5dBm
• Sensitivity: -100dBm
• Voltage - Supply: 1.8 V ~ 3.6 V
• Current - Receiving: 12.5mA
• Current - Transmitting: 14.5mA
• Data Interface: PCB, Surface Mount
• Memory Size: 128kB Flash, 4kB EEPROM, 16kB RAM
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-VFQFN, Exposed Pad
• Rf Ic Case Style: QFN
• No. Of Pins: 64
• Supply Voltage Range: 1.8V To 3.6V
• Operating Temperature Range: -40°C To +85°C
• Svhc: No SVHC (15-Dec-2010)
• Rohs Compliant: Yes
• Processor Series: ATMEGA128x
• Core: AVR8
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 128 KB
• Data Ram Size: 16 KB
• Interface Type: JTAG
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 38
• Number Of Timers: 6
• Operating Supply Voltage: 1.8 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVR128RFA1-EK1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

19.4 Register Description
19.4.1 GTCCR – General Timer/Counter Control Register
306
ATmega128RFA1
Enabling and disabling of the clock input must be done when Tn has been stable for at
least one system clock cycle. Otherwise there is a risk of generating a false
Timer/Counter clock pulse.
Each half period of the applied, external clock must be longer than one system clock
cycle to ensure correct sampling. The external clock must be guaranteed to have less
than half the system clock frequency (f
the edge detector uses sampling, the maximum frequency of a detectable external
clock is half the sampling frequency (Nyquist sampling theorem). However due to
variation of the system clock frequency and duty cycle caused by Oscillator source
(crystal, resonator and capacitors) tolerances, it is recommended to limit the maximum
frequency of an external clock source to less than f
can not be prescaled.
Figure 19-2. Prescaler for synchronous Timer/Counters
• 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 PSRASY and PSRSYNC bits is kept, hence
keeping the corresponding prescaler 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 the configuration. When the TSM bit is
written to zero, the PSRASY and PSRSYNC bits are cleared by hardware and the
Timer/Counters simultaneously start counting.
• Bit 6:2 – Res4:0 - Reserved
PSR10
clk
Bit
$23 ($43)
Read/Write
Initial Value
CSn0
CSn1
CSn2
Tn
Tn
I/O
Synchronization
Synchronization
TSM
RW
7
0
Res4
R
6
0
TIMER/COUNTERn CLOCK SOURCE
Res3
R
5
0
clk
Clear
Tn
Res2
ExtClk
R
4
0
< f
Res1
clk_I/O
R
3
0
/2) given a 50/50% duty cycle. Since
clk_I/O
Res0
CSn0
CSn1
CSn2
R
2
0
/2.5. An external clock source
PSRASY PSRSYNC
TIMER/COUNTERn CLOCK SOURCE
R
1
0
8266B-MCU Wireless-03/11
RW
0
0
clk
Tn
GTCCR