Multi-Tech Systems ISIHP-4SD, ISIHP-4U manual = 0, 1, 2, 3, 4, 5, 6, or

Modem AT Commands & S-Registers

V0 (or V) displays the modem’s result codes as a number.

V1 displays result codes as text.

V2, an additional command given anytime after ATV1 is entered, displays the connect message of both the local modem and the remote modem.

Xn	Result Codes and Call Progress Selection
	n = 0, 1, 2, 3, 4, 5, 6, or 7
	Default: X4

Selects which result codes the modem provides in command mode and determines whether the modem uses smart dialing or blind dialing. When it smart dials, the modem listens for dial tones and busy signals and responds to them. When it blind dials, the modem ignores the signals and relies on timing instead.

X0 causes the modem to blind dial. Instead of looking for a dial tone, it pauses for the time set in register S6 and then dials regardless. Once a connection is made, it sends the basic code CONNECT to the terminal. It ignores any busy signals.

X1 causes the modem to blind dial. In addition to the basic CONNECT code, it provides extended codes consisting of the word CONNECT and the speed of the connection (CONNECT 14400 or CONNECT 28800, for example). In this mode, the modem does not recognize or respond to dial tones or busy signals.

X2 causes the modem to wait for a dial tone before dialing. If it does not detect a dial tone within the time set by S6, the modem sends a NO DIALTONE result code to the terminal. In this mode, the modem provides extended result codes but does not respond to busy signals.

X3 causes the modem to blind dial and to look for a busy signal. If it detects one, it sends a BUSY result code to the terminal. In this mode, the modem provides extended result codes, but it does not respond to dial tones.

X4 causes the modem to look for a dial tone and a busy signal and respond with NO DIALTONE or BUSY, as appropriate. It also provides extended result codes. It is the most useful setting for most data communication programs and is the default setting.

X5 causes the modem to look for a dial tone and a busy signal and respond

MultiModemISI Hybrid Series, ISIHP-2S/2U/4S/4U/4SD 83