Toshiba TC9349AFG Manual page 119

IF monitor
Y1 Y2
φ K17
BUSY
MANUAL
φ K12 φ K13
Y1 Y2 Y4 Y8 Y1
F0 F1 F2 F3 F4
0
2
LSB
The IF counter calculates the IF signals usually from the tuner and detects the auto stop signal. When the IFin bit is set to
"1", the IFin input amplifier will operate and the IF counter will be enabled. The gain of the input amplifier can be
changed by the amplifier setting register port ( φ L16 (F), φ K11 (F)). Set this register to all "1". In the PLL off mode, this
amplifier is disabled and the IFin input becomes high impedance.
The IF input frequency range varies depending on the NC bit. When the NC bit is set to "1", the internal noise cancel
circuit operates. When the NC bit is "0", the frequency range is 0.35 to 12 MHz. When the NC bit is "1", the noise cancel
circuit operates and the frequency range is 0.03 to 1 MHz. Set this bit depending on the IF frequency to be detected.
The IF counter has two counting methods; namely the automatic and manual IF counter modes respectively. Counting is
carried out using the following methods:
(1) Automatic IF counter mode
To select the automatic mode for the IF counter, set the MANUAL bit to "0", and specify the gate time depending
on the frequency band to be measured. When the
clock will be inputted during the specified gate time, the number of these input pulses will be counted, and the
counter will stop the operation. Whether or not the IF counter has finished counting can be checked by referring to
the BUSY bit. The OVER bit becomes "1" when there is a pulse input a measured value of 2
The frequency being inputted can be measured by checking that the BUSY and OVER bits are set to"0" and
loading the IF data of F0 to F19.
(2) Manual IF counter mode
Use this mode when the frequency is measured by controlling the gate time using the internal time base (for
example, 10 Hz). Set the MANUAL bit to "1" to activate the manual mode. At this time, the gate time setting reverts
to "don't care" state. Counting starts by setting the
counting is finished and the data is loaded in binary format.
Y4 Y8
OVER 0
Overflow detection
Operation mode
Operation monitor
φ K14
Y2 Y4 Y8 Y1 Y2
F5 F6 F7 F8 F9
IF counter data
STA/
119
0: IF counter measured value < = 2
1: IF counter measured value > = 2
0: IF counter automatic mode
1: IF counter manual mode
0: IF counter measurement finished
1: IF counter measuring
φ K15
Y4 Y8 Y1 Y2 Y4
F10 F11 F12 F13 F14 F15
STP
bit is set to "1", the IF counter will start operation, the
STA/ STP
bit to "1". By setting the
TC9349AFG
20 − 1
20
(overflow state)
φ K16
Y8 Y1 Y2 Y4 Y8
F16 F17 F18 F19
19
2
MSB
20
or over.
STA/ STP
bit to "0",
2006-02-24