Masking Of Reception Data For Ir Decoder Echo Cancellation; Table 4-2. Pulse_Width[7:0] Setting Examples; Table 4-3. Mask_Period[19:0] Setting Examples - Renesas EMMA Mobile 1 User Manual

Desired Valid f = 1.8432 MHz
XIN
Reception
PULSE_
Pulse Width
WIDTH[7:0]

( s)

Note
1.0

Note
1.41
2.0 2
3.0 4
Note The desired pulse width cannot be detected because the XIN clock frequency is low.
The lower limit of the XIN clock frequency for the desired valid reception pulse width is obtained using the
following expression, by assigning the PULSE_WIDTH[7:0] value (= 2, the minimum setting) to the valid
reception pulse width expression.
(MHz)  1 /(desired valid reception pulse width (
f
XIN
Remark f : Frequency of reference clock (XIN)
XIN

4.6.3 Masking of reception data for IR decoder echo cancellation

The IR decoder can mask reception data (stop pulse detection) during transmission for echo cancellation. The
mask period can be extended for the transmission period plus the period specified by the IRCR2 to IRCR4 registers
(MASK_PERIOD[19:0]).
(IR_MASK_OFF) of the IRCR0 register.
Desired f = 1.8432 MHz
XIN
Mask
MASK_
Extension
PERIOD

Period ( s)
[19:0]
50 91
100 183
1,000 1,842
5,000 9,214
10,000 18,430
CHAPTER 4 DESCRIPTION OF FUNCTIONS

Table 4-2. PULSE_WIDTH[7:0] Setting Examples

f = 3.072 MHz
XIN
Measured PULSE_
Valid WIDTH[7:0]
Reception
Pulse Width

( s)

Note
2

Note
3
1.63 5
2.71 8
Whether to enable masking of the reception data can be specified by using bit 6

Table 4-3. MASK_PERIOD[19:0] Setting Examples

f = 3.072 MHz
XIN
Measured MASK_
Mask PERIOD
Extension [19:0]

Period ( s)
50.46 152
100.37 306
1000.43 3,070
5,000 15,358
10,000 30,718
User's Manual S19262EJ3V0UM
f = 14.7456 MHz
XIN
Measured PULSE_ Measured
Valid WIDTH[7:0]
Reception Reception
Pulse Width Pulse Width

( s)
0.98 13
1.30 19
1.95 28
2.93 43

s) / 3)
f = 14.7456 MHz
XIN
Measured MASK_ Measured
Mask PERIOD
Extension [19:0] Extension

Period ( s) Period (
50.13 736
100.26 1,473
1,000 14,744
5,000 73,726
10,000 147,454
f = 50 MHz
XIN
PULSE_ Measured
Valid WIDTH[7:0]
Reception
Pulse Width

( s)
0.95 49
1.36 69
1.97 99
2.98 149
f = 50 MHz
XIN
MASK_ Measured
Mask PERIOD
[19:0] Extension

s) Period (
50.05 2,498
100.03 4,998
1,000.03 49,998
5,000 249,998
10,000 499,998 10,000
Valid

( s)
1.0
1.41
2.0
3.0
Mask

s)
50
100
1,000
5,000
43