Basic Modem Operation 23
your software supports it, replace the 16450 UART with a 16550
model. This newer chip has an internal buffer and generates an
interrupt for up to every 16 characters (several trigger levels are
available). With this UART installed, you may drive your serial port
at 57600 bps and above.
While data is written from the transfer-buffer to your hard-disk,
characters may be lost at the serial port. This is due to the fact that
disk-access interrupts have a higher priority than serial port
interrupts. If you are running at a high serial speed, e.g. 230.4Kbps
or 460.8Kbps, on your PC, be sure to enable the disk cache by
including SMARTDRV execution in your AUTOEXEC batch file.
Default Modem Settings for PC
’
s
The U-336S factory settings are configured for operation with PC
type computers and communication software. In most cases, no
additional settings will be required. The following are some of the
default settings that are used for operation with PC computers and
software:
AT Command
Description
E1
Echoes command characters.
&C1
Carrier detect follows remote carrier.
&D2
Modem disconnects on DTR on-to-off
transition.
&K4
Use both V.42 and MNP 4 error correction, and
use both V.42bis and MNP 5 data compression.
&N0
Modem negotiates highest possible connection
speed.
ZyXEL Serial/Parallel I/O Card
For high-speed PC to modem communication, ZyXEL produces a
special I/O adapter card. This card includes a serial port and a
Содержание U-336S
Страница 1: ...U 336S User s Manual Version 2 0 Mar 1997 ZyXEL ACCESSING INTERNET INTRANET ...
Страница 18: ...6 Introduction ...
Страница 24: ...12 Installation ...
Страница 72: ...60 Special Functions ...
Страница 98: ...86 Fax Operation ...
Страница 115: ...AT Command Set Summaries 103 ...
Страница 138: ...126 Status Registers Result Codes Numerical V0 Verbose V1 Numerical V0 Verbose V1 14400 33600 ...
Страница 139: ...Status Registers Result Codes 127 ...
Страница 157: ...Connector Pinouts 145 ...