AT Commands Reference Manual - wireless netcontrol GmbH

Call Control
Assistant (CA) will type back exactly what is said and it will appear on the screen of your
TTY or VCO phone.
HCO: Hearing Carry Over allows Speech Disabled callers who can hear well on the
telephone to listen directly to the person they are talking with. The Speech Disabled Relay
user types his or her part of the conversation on a TTY. A Communication Assistant (CA)
then speaks the typed conversation, word for word, to the standard telephone user.
Figure 3-1 shows the TTY hardware configuration.
Figure 3-1: TTY Hardware Configuration
Example
AT+MTTY=?
+MTTY: (1-3)
OK
AT+MTTY=1
OK
AT+MTTY?
+MTTY: 1
OK
3-44 H24 - AT Commands Reference Manual April 15, 2010