2001 Jun 19

16

Philips Semiconductors

Preliminary specification

Bluetooth Adapter IC

PCF26100

Table 21 Register values range and actual timings

6.5.5

RSSI

The RSSI is read via the serial interface. The UAA3558 provides an analog RSSI output. The interface logic converts the

analog RSSI value and stores the result in a serial interface register. The timing for converting the RSSI is programmed

using the RSSI_start register. The RSSI can only be measured starting 10

µs after the S_EN falling edge. The RSSI

value can only be read from the serial interface register after the measurement has been completed, this is at the end of

the packet. RSSI measurements are only done in receive packets.

Table 22 RSSI control word

6.5.6

The transmit power can be controlled from a serial interface register. The 8-bit transmit power control word is used to

control the PA DAC. Writing to the PA DAC register will directly change the PA DAC output. The PA control register

should be written when the transmitter is not active.

Table 23 Unidirectional JTAG PA control word

6.5.7

The values for the GFSK filter are stored in a 13-byte GFSK table. The GFSK table is accessed through a single control

word which is used to store the data in the GFSK table on subsequent writes. To align the writing to the GFSK table a

table address reset bit is available in the Enable register. When the reset bit ‘grst’ in the Enable register is set to a logic 1

the GFSK table address will be reset and the next GFSK control word is written at location 0 in the GFSK table. Every

subsequent write to the GFSK control word will be stored at the next address in the GFSK table. If the last address is

reached, subsequent writes will continue to effect the last address.

of 1.2 V with a peak-to-peak swing of 1 V (amplitude = 0.5 V). For this the values for the GFSK table are calculated as

shown in Table 26.

Table 24 Unidirectional JTAG GFSK control word

REGISTER

RANGE

TIMING

ACTUAL VALUE

UNIT

S_EN_START

0 < x < 256

S_EN_START + (0 to 1)

µs

S_EN_WIDTH

0 < x < 256

S_EN_WIDTH

µs

T_SW_START

S_EN_START < x < 256

T_SW_START + (0 to 1)

µs

SLCCTR_START

0 < x < 256

SLCCTR_START + 1

µs

S_EN_PULSE_DEL

0 < x < 256

S_EN_PULSE_DEL + (0 to 1)

µs

RSSI_START

0 < x < 256

RSSI_START

µs

GFSK_DC_BIAS

0 < x < 256

GFSK_DC_BIAS + (0 to 1)

µs

ADDRESS

76543210

18 (decimal)

RSSI

ADDRESS

76543210

24 (decimal)

PA power control

GFSK_TABLE

76543210

28 (decimal)

GFSK table value