This service is used to send or receive data packets to or from Siemens programmable controllers.

To send or receive a message, one has to define the unsolicited TSAP by specifying the name of the unsolicited TSAP in the /NETADDR definition of the Siemens device.

You can use the following program to send data to the programmable controller, using an unsolicited TSAP.

#include stdio #include stdlib #include ssdef #include <ilan_defs> #include <ilan_services> #include <dcm_h1$def> main () { long int ret; char *device_name = "S150_DEVICE"; long int send_function = dcm_h1$k_send_message; /* Send message */ short int ret_length; unsigned char request_buffer[512]; unsigned char *null_buffer = NULL; short int request_buffer_len; short int response_buffer_len; request_buffer_len = 10; response_buffer_len = 0; ret = ilan_device_specific (0, device_name, &send_function, &request_buffer_len, (struct itmlst *) request_buffer, &response_buffer_len, (struct itmlst *) null_buffer, &ret_length); exit (ret); } /* End main */

You can use the following program to receive data from the programmable controller, using an unsolicited TSAP.

#include stdio #include stdlib #include <ilan_defs> #include <ilan_services> #include <dcm_h1$def> main () { long int ret; char *device_name = "S150_DEVICE"; long int rcv_function = dcm_h1$k_receive_message; /* Receive message */ short int ret_length; unsigned char request_buffer[512]; unsigned char response_buffer[512]; unsigned char *null_buffer = NULL; short int request_buffer_len; short int response_buffer_len; request_buffer_len = 0; response_buffer_len = sizeof (response_buffer); ret = ilan_device_specific (0, device_name, &rcv_function, &request_buffer_len, (struct itmlst *) null_buffer, &response_buffer_len, (struct itmlst *) response_buffer, &ret_length); exit (ret); } /* End main */