CONTROLINK86 SMSC, CONTROLINK86 Datasheet - Page 15

• Manufacturer Part Number: CONTROLINK86
• Description: Development Software Embedded Networking Software
• Manufacturer: SMSC

Specifications of CONTROLINK86

• Tool Function: Compiler
• Tool Type: Compiler
• Processor Series: 80x86
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ControLink86 Realtime Networking Software
2.5EXECUTING CONTROLINK
Running ControLink is simple. Real-time systems often operate using a rotating scheduler calling several
routines at defined intervals. ControLink is designed to operate in such an environment. The Class 1
driver contains a routine called llc1_service(). llc1_service() is the key to proper and timely operation of
the network. As packets arrive at the node, the hardware interrupts the system. ControLink’s low level
driver contains an interrupt handler that buffers the packet onto a queue maintained in system memory
and enables reception of another packet. Messages remain queued until the host system calls
llc1_service(). At this time, llc1_service reads the first packet from the top of the queue. llc1_service()
decodes the header information from the packet and makes a decision based on this information. The
following occurs for different services:
Incoming messages will not be processed without calling llc1_service() first.
2.5.1CHECKING SAPS FOR INCOMING MESSAGES
ControLink provides a convenient method of checking each SAP buffer for new messages. The
llc1_indication() routine is used for checking the SAP for new messages. For group addresses use the
llc1_group_indication() routine.
Example: (check SAP 4 for messages)
•
•
•
Node Identification - reception of this command causes an automatic response message from
the Class 1 state machine and buffers the message into the SAP specified in the dsap field of the
packet. This service is used to identify what class of LLC services is supported by the tested
station. See section 3.6.2.2.)
Link Test - reception of this command causes an automatic response message from the Class 1
state machine and buffers the message into the SAP specified in the dsap of the packet. The
reply is scheduled as early as possible. This is used to test the connection between the stations.
(See section 3.6.2.3.)
Basic Message Transfer - message is placed in the SAP buffer corresponding to the dsap
address found in the packet header and sets an indication flag to the host. (See section 3.6.2.4.)
…
/* initialize Class 1 state machine with local SAP */
status = llc1_request(0,0,ENABLE_WITHOUT_DUP_ADDR_CHECK, &SAP0);
if (status == E_OK)
…
} /* end main */
{
status = llc1_request(1,0, SAP_ACTIVATION_REQUEST, &SAP1);
if (status == E_OK)
else
GSAP1.group = 1;
status = llc1_request(1,0, SAP_ACTIVATION_REQUEST, &GSAP1);
if (status == E_OK)
else
}
{
printf(“SAP 1 is up\n”);
}
{
printf(“Error in activating SAP 1\n”);
}
{
printf(“GSAP 1 is up\n”);
}
{
printf(“Error in activating GSAP 1\n”);
}
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