IRCC SMSC Corporation, IRCC Datasheet - Page 11

• Manufacturer Part Number: IRCC
• Description: INFRARED COMMUNICATIONS CONTROLLER
• Manufacturer: SMSC Corporation

The Transmit and Receive Bit Rate Divider
register is used to extract a serial NRZ data
stream for the IrCC SCE. The divider is eight bits
wide.
The input clock to the Bit Rate Divider is 100KHz
(Carrier Frequency Divider input clock ÷ 16).
The
relationship
BRD
003
007
011
015
019
023
027
031
035
039
043
047
051
055
059
063
between
Fb (KHz)
25.000
12.500
8.333
6.250
5.000
4.167
3.571
3.125
2.778
2.500
2.273
2.083
1.923
1.786
1.667
1.563
the
Table 10 - Representative Bit Rates
BRD
067
071
075
079
083
087
091
095
099
103
107
111
115
119
123
127
Bit
Fb (KHz)
1.471
1.389
1.316
1.250
1.190
1.136
1.087
1.042
1.000
0.962
0.926
0.893
0.862
0.833
0.806
0.781
Rate
11
BRD
131
135
139
143
147
151
155
159
163
167
171
175
179
183
187
191
For example, program the Bit Rate Divider with
55 ('37'Hex) for a .562ms TV Remote bit cell: Fb
= 1.786KHz. This is ~.5% accuracy. Table 10
contains representative BRD vs. Bit Rate
relationships. The Bit Rate range is 100KHz to
390.625Hz.
Fb (KHz)
0.758
0.735
0.714
0.694
0.676
0.658
0.641
0.625
0.610
0.595
0.581
0.568
0.556
0.543
0.532
0.521
BRD = (.1MHz/Fb) - 1
BRD
195
199
203
207
211
215
219
223
227
231
235
239
243
247
251
255
Fb (KHz)
0.510
0.500
0.490
0.481
0.472
0.463
0.455
0.446
0.439
0.431
0.424
0.417
0.410
0.403
0.397
0.391