SLOS758G December 2011 – March 2020 TRF7963A
Table 6-25 describes the bit fields of the RX Special Setting register. This register sets the gains and filters directly. When bits B7, B6, B5, and B4 are all zero, the filters are set for ISO/IEC 14443B (240 kHz to 1.4 MHz).
Default Value: 0x40, set at POR = H or EN = L and at each write to the ISO Control register (0x01)
|BIT NO.||BIT NAME||FUNCTION||DESCRIPTION|
|B7||C212||Band-pass 110 kHz to 570 kHz||Appropriate for 212-kHz subcarrier system (FeliCa)|
|B6||C424||Band-pass 200 kHz to 900 kHz|
|B5||M848||Band-pass 450 kHz to 1.5 MHz||Appropriate for Manchester-coded 848-kHz subcarrier used in ISO/IEC 14443 A|
|B4||hbt||Band-pass 100 kHz to 1.5 MHz
Gain reduced for 18 dB
|Appropriate for highest bit rate (848 kbps) used in high-bit-rate ISO/IEC 14443|
|B3||gd1||00 = Gain reduction 0 dB
01 = Gain reduction for 5 dB
10 = Gain reduction for 10 dB
11 = Gain reduction for 15 dB
|Sets the RX gain reduction and reduces sensitivity|
The setting of bits B4, B5, B6, and B7 to zero selects band-pass characteristic of 240 kHz to 1.4 MHz. This is appropriate for ISO/IEC 14443 B, FeliCa protocol, and ISO/IEC 14443 A higher bit rates (212 kbps and 424 kbps).