Z0220516SSGR4259 Zilog, Z0220516SSGR4259 Datasheet - Page 13
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Z0220516SSGR4259
Manufacturer Part Number
Z0220516SSGR4259
Description
IC MODEM CTRL 86E34 28-SOIC
Manufacturer
Zilog
Specifications of Z0220516SSGR4259
Data Format
V.22
Baud Rates
2.4k
Interface
Serial
Voltage - Supply
4.5 V ~ 5.5 V
Mounting Type
Surface Mount
Package / Case
28-SOIC (7.5mm Width)
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
ZiLOG
PS001000-MOD0599
Command
A
B
&C
Answer
Communication Standard
Option
Data Carrier Detect
Options
Function and Description
The A command causes the modem go off-hook and respond to an incoming call. Uses
this command after the modem has returned the RING result code.
When modems successfully complete the answering process, they each return a
CONNECT result code and enter the On-Line state.
If no transmit carrier signal is received from the calling modem within the time specified
in S-register S7, the modem hangs up, returns the NO CARRIER result code, and enters
the Idle state.
Any commands following the answer command on the command line are ignored.
This command is aborted if a key is pressed before the answer process is completed, or
when DTR is off, if some options in the &Q or &D commands have been used.
The B command indicates to the modem which special telephone line modulation
standards to use. The modem can be configured to use:
B0
B1
B2
B3
&C determines how the modem’s DCD signal relates to the carrier signal from the other
modem. This option occurs only at the beginning of a telephone line connection. If &C is
issued from the Command state, it will not have an immediate effect.
&C0
&C1
Table 2. AT Command Set
Uses the ITU-T modulation standards for all telephone line data rates. This
includes V.22 for the 1200 bps telephone line data rate and V.21 for the 300
bps telephone line data rate. If S-register S37 is set to 1 (or 2), then V.23 is
used with the originating modem transmitting at 75 bps and receiving at
1200 bps. If S-register S37 is set to any other value, V.23 is not used.
If the 1200 bps telephone line data rate is required, Bell 212A is used
instead of V.22. This is the default value for North America. The 1200 bps
telephone line data rate is required only if:
• S-register S37 is set to 5, or
• S-register S37 is set to 0, and the terminal data rate is 1200 bps.
If the 300 bps telephone line data rate is required, Bell 103 is used instead
of V.21. The 300 bps telephone line data rate is required only if:
• S-register S37 is set to 3, or
• S-register S37 is set to 0 and the terminal data rate is 300 bps.
If neither the 1200 bps nor 300 bps telephone line data rate are required,
then a setting of B1 is ignored and the modem responds as if B0 was set.
Same as B0 for the 1200 bps and 300 bps telephone line date rate. Uses
V.23 with the originating modem transmitting at 1200 bps and receiving at
75 bps, if S-register S37 is set to 1 or 2.
Same as B0 for the 1200 bps and 300 bps telephone line date rate. Uses
V.23 with the originating modem transmitting at 75 bps and receiving at
1200 bps, if S-register S37 is set to 1 or 2.
During asynchronous operation (&Q0 in effect), DCD is on at all times.
During synchronous operation (&Q1), DCD indicates the state of the
carrier signal from the other modem using S-registers S9 and S10. This is
the default value in North America.
Indicates the state of the carrier signal from the other modem using S-
registers S9 and S10.
Modem Controller
Z02205
11