Installation Manual

IRIS OEM Edition Hardware Reference Manual
Doc. # 7430-0549-01 Rev. B Page 17
Table 4-3. Internal Calibrated RC Oscillator Operating Modes
CKSEL[3..0] Nominal Freq Range (MHz)
0010 7.3 – 8.1
4.3.2 System Clock Prescaler
The processor has a system clock prescaler, and the system clock can be divided by setting the
“Clock Prescale Register - CLKPR” as shown in Table 4-4. This feature can be used to reduce
the system frequency and the power consumption when the requirement for processing power is
minimized.
Table 4-4.Clock Prescaler Select
CLKPS[3..0] Clock Division Factor
0000 1
0001 2
0010 4
0011 8
0100 16
0101 32
0110 64
0111 128
1000 256
1001 – 1111 Reserved
4.3.3 128 kHz Internal Oscillator
The 128 kHz internal Oscillator is a low power Oscillator providing a clock of 128 kHz. The
frequency is nominal at 3V and 25
℃. This clock maybe selected as the system clock by
programming the CKSEL fuses to “11” as show in Table 4-6.
Table 4-5 128 kHz Internal Oscilator Operating Modes
CKSEL[3..0] Nominal Freq (kHz)
0011 128
More information is available in the datasheet for Atmel’s ATmega1281 processor.
4.4 Solder Profile
4.4.1 Hand-soldering
Instructions for Hand Soldering of Crossbow OEM Module are provided below.
Method 1:
1)
Pre-tin the surface mount pads on the board the OEM module will be soldered to. Be
careful to use an equal amount of solder on each pad.