z02201 ZiLOG Semiconductor, z02201 Datasheet - Page 61

• Manufacturer Part Number: z02201
• Description: Z02201 V.22bis Data Pump With Integrated Afe
• Manufacturer: ZiLOG Semiconductor

Dialing
PS000904-0107
Tone Dialing
Notes:
The data pump may be programmed to dial using either DTMF tones, or make/
break pulses. By default, the data pump is configured for tone (DTMF) dialing.
Tone dialing may be either continuous or timed. Continuous dialing generates the
required tone until the host specifically shuts it OFF. Timed dialing allows the host
to specify the on/off timing of the digit dialed.
The following example assumes the host controls the data pump’s RTS through
Reg4, bit 3 (RTSP). To perform tone dialing:
1. Set Reg4, bit
2. Control the twist by setting locations DTMFH_LEV and DTMFL_LEV to specify
dialing, or to
3
SEQ2COUNT to
the transmit levels of the high tone and the low tone, respectively.
(DIAL). If timed dialing is required, set the timer locations SEQ1COUNT and
Failing to program the notch filter to the same frequency as
the transmitted tone when CONFIG register, bits 0–6 (MODE)
is
pump's tone detectors.
It is not possible to generate two tones simultaneously when
CONFIG register, bits 0–6 (MODE) is
reducing the accuracy and sensitivity of the data pump's tone
detectors, even if the notch filter is programmed to remove
one of the generated tones.
The notch filter attenuates received signals at frequencies
close to the notched frequency. For the commonly used
coefficient values shown, signals within 100 Hz of the notch
frequency are attenuated by 6 dB or more, signals 320 Hz or
more from the notch frequency are attenuated by less than
1 dB.
4
seriously reduces the accuracy and sensitivity of the data
0
3
for continuous dialing. Set CONFIG register, bits 0–6 (MODE) to
1
(RTSP) to
.
0
, TONESTATUS, bit
V.22BIS Data Pump with Integrated AFE
4
4
(TIMEDIAL) to
without seriously
1
for timed
57