Intel 536EX manual Intel Confidential, AT Command Summary Tables, Voice DTE←DCE Character Pairs

			AT Command Summary Tables
Table 10. Voice DTE→DCE Character Pairs (Continued)
	Response	Hex Code	Function
	<DEL>	7F	DTMF transition to off
	u	75	Bump up the volume
	d	64	Bump down the volume
	<ESC>	1B	End receive data state
	!	21	Receive data abort
	<CAN>	18	Clear transmit buffer of voice data
	?	3F	Transmit buffer space available query

Table 11. Voice DTE←DCE Character Pairs

Response	Hex Code	Function
<DLE>	10	Single <DLE> character in the data stream
<SUB>	1A	<DLE><DLE> in data stream
<ETX>	3	End of Record mode data
X	58	Packet header for ‘Complex Event Detection Report’
.	2E	Packet terminator for the ‘Complex Event Detection Report’
/	2F	Start of DTMF tone shielding
<DEL>	7F	DTMF transition to off
0–9	30–39	DTMF tones 0–9
A–D	41–44	DTMF tones A–D
*	2A	DTMF tone *
#	23	DTMF tone #
o	6F	Receive buffer overrun
c	63	1100 Hz fax calling tone
e	65	1300 Hz data calling tone
h	68	Local phone goes on hook
H	48	Local phone goes off hook
s	73	Presumed hang-up silence time-out
q	71	Presumed end-of-message quiet time-out
I	6C	Loop current interruption
L	4C	Loop current polarity reversal
r	72	Ringback
b	62	Busy/reorder/fast busy
d	64	Dial tone detected
u	75	Transmit buffer under-run
p	70	Line voltage increase (extension phone goes on-hook)
P	50	Line voltage decrease (extension phone goes off-hook)
a	61	Fax or data answer tone (2100 Hz)

536EX Chipset Developer’s Manual 23

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