Rockwell RCV144ACx, Command Reference Manual

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AT Command Reference Manual
1048 6-1
6. FAX CLASS 2 COMMANDS
The fax class 2 commands are summarized in Table 6-1.
6.1 COMMAND SYNTAX AND GUIDELINES
6.1.1 DTE Commands
The ISO 646 character set (CCITT T.50 International Alphabet 5, American Standard Code for Information Interchange) is
used for the issuance of commands and responses. Only the low-order 7 bits of each character are used for commands or
parameters; the high order bit is ignored. Upper case characters are equivalent to lower case characters.
For Phase C data transmission or reception, all 8 bits are needed.
DTE Command Lines
A command line is a string of characters sent from a DTE to the modem (DCE) while the modem is in a command state. A
command line has a prefix, a body, and a terminator. Each command line (with the exception of the A/ command) must
begin with the character sequence AT and must be terminated by a carriage return. Commands entered in upper case or
lower case are accepted, but both the A and T must be of the same case, i.e., "AT" = ASCII 065, 084 or “at” = ASCII 097,
116. The body is a string of commands restricted to printable ASCII characters (032 - 126). Space characters (ASCII 032)
and control characters other than CR (ASCII 013) and BS (ASCII 010) in the command string are ignored. The default
terminator is the ASCII <CR> character. Characters that precede the AT prefix are ignored. The command line interpretation
begins upon receipt of the carriage return character.
Facsimile Command Syntax
After the "AT" or "at" prefix, facsimile commands use extended syntax. Each command is preceded by the “+F” character
and consists of single characters and a decimal parameter (if applicable) terminated by the semicolon “:” character (ASCII
059) or by the <CR> that terminated the command line. A missing decimal parameter is evaluated as 0.
For example, the command to instruct the modem to automatically answer a data or fax call and also enable reception is:
AT+FAE=0; +FCR 1 <CR>
Basic data mode and fax service class mode select commands are:
AT+FCLASS=0 <CR> for Data Mode
AT+FCLASS=1 <CR> for Service Class 1 Fax
AT+FCLASS=2 <CR> for Service Class 2 Fax
In Class 2, the DCE makes and terminates calls, manages the communication session and negotiates (T.30 protocol) and
transports the image date to DTE. The T.4 protocol management of image data, etc., is done by DTE.
The response to
AT+FCLASS= 0<CR> in Data Mode
or
AT+FCLASS=2<CR> in Service Class 2 Fax
is
OK
The service class may be set by the DTE from the choices available using the “+FCLASS=<VALUE>” command.
General Rules
1. +Fnnn commands must be entered completely, otherwise an ERROR response is sent.
2. All response messages are preceded and followed by <CR><LF>. Multiple response commands (e.g., +FDIS: +FCSI:
and +FDCS:) will, therefore, appear to a have a blank line between them.