Advertisement
3.
Set the REMC3DBCTL.MODEN bit to 0.
18.4.3. REMO Output Waveform
Carrier refers to infrared frequency in infrared remote control communication. Note, however, that
carrier in this manual refers to sub-carrier used in infrared remote control communication, as REMC3
does not control infrared rays directly.
The REMC3 outputs the logical AND between the carrier signal output from the carrier generator and
the data signal output from the data signal generator. Figure 18.4.3.1 shows an example of the output
waveform.
Carrier signal
Data signal (Modulated data)
REMO output
REMC3CCTL.
REMC3DBCTL.
OUTINVEN bit
REMOINV bit
0
0
1
1
Carrier signal
The carrier signal is generated by comparing the values of the 8-bit counter for carrier generation that
runs with CLK_REMC3 and the setting values of the REMC3CARR.CRDTY[7:0] and
REMC3CARR.CRPER[7:0] bits. Figure 18.4.3.2 shows an example of the carrier signal generated.
Example) REMC3CARR.CRDTY[7:0] bits = 2, REMC3CARR.CRPER[7:0] bits = 8
CLK_REMC3
8-bit counter for
carrier generation
Carrier signal
The carrier signal frequency and duty ratio can be calculated by the equations shown below.
Carrier frequency =
Where
f
: CLK_REMC3 frequency [Hz]
CLK_REMC3
CRPER: REMC3CARR.CRPER[7:0] bit-setting value (1–255)
CRDTY: REMC3CARR.CRDTY[7:0] bit-setting value (0–254)
* REMC3CARR.CRDTY[7:0] bits < REMC3CARR.CRPER[7:0] bits
The 8-bit counter for carrier generation is reset by the REMC3DBCTL.PRESET bit and is started/stopped
by the REMC3DBCTL.PRUN bit in conjunction with the 16-bit counter for data signal generation. When
the counter value is matched with the REMC3CARR.CRDTY[7:0] bits, the carrier signal waveform is
inverted. When the counter value is matched with the REMC3CARR.CRPER[7:0] bits, the carrier signal
waveform is inverted and the counter is reset to 0x00.
Data signal
18-4
0
1
0
1
Figure 18.4.3.1 REMO Output Waveform Example
0
1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 0 1 2 3 4
Figure 18.4.3.2 Example of Carrier Signal Generated
��
������_REMC3
���������� + 1
Seiko Epson Corporation
(Disable count operation clock)
Data bit
A
B
���������� + 1
Duty ratio =
���������� + 1
(����. 18.1)
S1C31D50 TECHNICAL MANUAL
(Rev. 1.00)
Advertisement
