Z0221500ZCO Zilog, Z0221500ZCO Datasheet - Page 25

• Manufacturer Part Number: Z0221500ZCO
• Description: Z02215 ONE-CHIP MODEM EVAL KIT
• Manufacturer: Zilog

Specifications of Z0221500ZCO

• Main Purpose: Telecom, Modem
• Utilized Ic / Part: Z02215
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Secondary Attributes: -
• Embedded: -
• Primary Attributes: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Z02215 Single-Chip Modem
Evaluation Board User Manual
19
before the modem takes the telephone line OFF-HOOK to dial a
number.
The Data Access Arrangement (DAA) provides a Line-In-Use circuit
for the modem, connected to the combined Ring Detection and Line-
In-Use input signal (RDET/LCS). There are two methods of
implementing the Line-In-Use circuit in a DAA. For serial phone
detect, the circuit only detects if a telephone in series with the modem
is OFF-HOOK. For parallel phone detect, the circuit detects if any
telephone on the line is OFF-HOOK, including telephones wired in
parallel to the modem. Serial and parallel phone detection schemes
require different hardware and firmware support.
To perform parallel phone detection, the modem activates the line
check circuit by driving the Line-Check output signal (LCS_CHK)
Active for a period of time (X). During this time, the modem
examines the Line- In-Use input signal (RDET/LCS). If the Line-In-
Use input remains active (0V) for a period of time (Y) while the Line-
Check output signal is active, the line is deemed to be in use and the
call is aborted.
To perform serial phone detection, the modem examines the Line-In-
Use input signal (RDET/LCS) for a period of time (X) without
activating the Line-Check output signal (LCS_CHK).If the Line-In-
Use signal stays active (0V) for a period of time (Y), within the check
period (X), the dial attempt is permitted. Otherwise, the line is
deemed to be in use, and the call is aborted.
Bit 7 of the Z02215_PARPHONE_DETECT parameter selects
whether parallel or serial phone detection is required. The Line-In-
Use function can be disabled by setting Bit 9 in
PttBitmap0
(LINE_SENSE_ENABLE) to
.
0
Setup and Installation
PRELIMINARY
UM002304-0802