MT3334HD8 User Guide
30 CommPlete Communications Server
&RnClear to Send Control
n
= 0, 1, or 2
Default: &R1
The &R command lets you control the state of the Clear to Send (CTS) signal on pin 5 of the RS-232/V.24
interface. Normally, CTS follows RTS when the modem is online. You have three choices. You can force the
signal high, allow it to act normally, or set it to stay high until the modem disconnects, go low
momentarily, and then go high again. The last option is useful wit h CBX phone systems and mainframe
front ends that require CTS to act in this manner.
&R0 lets CTS act normally, that is, to follow RTS.
&R1 forces CTS high. When the modem goes online, CTS still provides flow control.
&R2 lets CTS drop on disconnect for the time set by register S24, then go high again.
&SnData Set Ready Control
n
= 0, 1, or 2
Default: &S1
Use the &S command to control the state of the Data Set Ready (DSR) signal on the RS-232/V.24 int erface.
Normally, DSR follows CD. You can force the signal high; allow it to act normally; or set it to stay high until
the modem disconnects, go low momentarily, and then go high again.
&S0 forces DSR high.
&S1 allows DSR to act normally, that is, to follow CD.
&S2 sets up DSR so that it drops for one second on disconnect and then comes up again. (If you want to set
the drop time to something other than one second, change register S24.)
&RFnCTS/RTS Interaction Control
n
= 0 or 1
Default: &RF1
In normal operation, Clear to Send (CTS) follows Request to Send (RTS) when th e modem is online. In
other words, if RTS goes off, CTS goes off. In some applications, ho wever, it is necessary for CTS to operate
independently of RTS.
&RF0 enables CTS to follow RTS.
&RF1 enables CTS to operate independently of the state of RTS. See the &R command for control of CTS.
&SFnDSR/CD Interaction Control
n
= 0 or 1
Default: &SF0
Normally, the Data Set Ready (DSR) signal follows the Carrier Detect (CD) signal. In other words, if CD
goes high, DSR goes high. In some applications, however, it may be necessary for DSR to oper ate
independently of CD.
&SF0 enables DSR to follow CD.
&SF1 enables DSR to operate independently of CD. For control of DSR, see the &S command.