User`s guide

SLTA-10 Adapter User’s Guide
11-11
The length of modem-string is limited to the application and network buffer sizes
within the SLTA-10 Adapter node and the node which is communicating with it. The
SLTA-10 Adapter as shipped has buffers sizes allowing for a maximum of 46
characters in the modem string sent with this message.
The string must be null
terminated.
If a large string needs to be sent to the SLTA-10 Adapter, use a series of these
requests with a single carriage return in the last string. Note that many modems
have a limited input buffer size, typically 32 to 80 bytes.
The mode parameter is used to control the connection state of the SLTA-10 Adapter.
The values for this parameter are:
0 Make no change to the SLTA-10 Adapter’s modem connection state. Send only if
not CONNECTED. Otherwise, respond with a failed status.
1 Initiate a dial-out connection. If the SLTA-10 Adapter is already currently
connected, preserve that connection, and ignore the message. The SLTA-10
Adapter’s connection status changes from IDLE to CALL-IN-PROCESS, unless
the connection is already made, in which case the state stays at CONNECTED.
The dial-out prefix is sent first.
2 Same as ‘l’, but disconnect (hang-up) if currently connected before initiating the
new connection.
Modem Response Query
ASCII strings received from the modem when the SLTA-10 Adapter is not connected
to a host will be buffered and may be read back by a node via this message. The
storage for this string is limited, and so it will contain only the first 16 characters
received from the modem in the disconnected state. Executing the Send Modem
String message will always clear this buffered string. It will not be cleared when the
modem disconnects, aiding in diagnosis of connection problems.
typedef struct {
byte sub-code;
// always #I
byte app-command;
// value = 4
byte max-length;
// limits the size of the response.
1 ANM-modem-response-query-request;
typedef struct {
char response[];
// null terminated string
1 ANM-modem-response-query-response;