# BASEstartm Classic DAS
for Allen-Bradley
INTERCHANGEtm Software
Installation and User's Guide

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## 2.3.3 Setting the BASEstar Classic Message Port Quota Parameter

The DAS for AB INTERCHANGE software requires a message port quota of 100,000. The BASEstar Classic parameter BCC$MAX_PORT_QUOTA must be set greater than or equal to this value.

Use the BASEstar Classic CLI SHOW PARAMETER command to review the value of the maximum port quota parameter. If necessary, use the SET PARAMETER command to adjust it. For more information refer to the BASEstar Classic Configuration and Tuning Guide.

## 2.3.4 Setting the SPT Block Parameter

The ILAN$MAX_SPT_REQUESTS parameter specifies the total number of blocks that can be allocated in the SPT (support) global section. DASes use blocks in the global section for storing data structures and for doing device I/O. The SPT global section is sized by calculating the number of SMALL, MEDIUM, LARGE and EXTRA LARGE blocks that the section should contain. Some blocks remain for the life of a device and some are allocated and deallocated for each I/O operation. Table 2-6 shows the static blocks of each size that are used by the DAS.

Table 2-6 SPT Static Block Sizes
Block Size | Quantity1 | Block Type
--- | --- | ---
MEDIUM | 2 | Device
| 1 | Line
| 1 | DTL Server
| 1 | DAS
SMALL | 1 | Device 2
| 1 | Unsolicited point 2

1Quantity is quantity per device, per line, per server, etc.
2Only created if the device is marked "unsolicited".

Table 2-7 shows the dynamic blocks of each size that are used by the DAS. These blocks are created and deleted as the device does I/O.

Table 2-7 SPT Dynamic Block Sizes
Block Size | Quantity1 | I/O Type
--- | --- | ---
LARGE | 1 | Status
MEDIUM | 1 | Read 2, write 2, upload, download
SMALL | 3 | Any 3

1Quantity is quantity per I/O.
2Block size is dependent on the size of I/O. For data larger than ~345 bytes, block size will be LARGE.
3These blocks are created for any I/O operation.

The size of the SPT global section can be tuned by changing the percentage of each kind of block that is created. Refer to the BASEstar Classic Configuration and Tuning Guide for instructions on changing the percentage of each size of block that is created in the global section.

## 2.3.5 Setting DAS-Specific Parameters

The following sections describe how to set the following DAS-specific BASEstar Classic parameters:

- ILAN$DTLSRV_PRIORITY
- ILAN$DTL_BACKLOG
- ILAN$DTL_CYCLE_TIME
- ILAN$DTL_DWNL_FLAGS
- ILAN$DTL_MAX_ELEMENTS
- ILAN$DTL_MAX_UNSOL_ELEMENTS
- ILAN$DTL_SCMP_FLAGS
- ILAN$DTL_TIMEOUT
- ILAN$DTL_UDC_TIMEOUT
- ILAN$DTL_UPL_FLAGS
- ILAN$DTL_DUP_EI_ID

None of the parameters created for the DAS for AB INTERCHANGE software are dynamic. BASEstar Classic device connection management must be shut down and started again before parameter modifications become effective.

### 2.3.5.1 ILAN$DTLSRV_PRIORITY

The ILAN$DTLSRV_PRIORITY parameter sets the priority of the INTERCHANGE server process, DCM_DTL$SRV. Values are as follows:

Default value | 6
Minimum value | 1
Maximum value | 10

Use this parameter in conjunction with the ILAN$DTL_CYCLE_TIME parameter to balance the performance of the INTERCHANGE server process. A high priority setting will give more CPU time to the server process for collecting data and processing requests. Understand, however, that increasing this setting may be at the expense of the applications using this data. Refer to the appropriate documentation on OpenVMS system management and tuning for more information.

### 2.3.5.2 ILAN$DTL_BACKLOG

The ILAN$DTL_BACKLOG parameter sets the number of unsolicited messages which will be buffered by the INTERCHANGE software. Values are as follows:

Default value | 5 messages
Minimum value | 1 message
Maximum value | 40 messages

### 2.3.5.3 ILAN$DTL_CYCLE_TIME

The ILAN$DTL_CYCLE_TIME parameter controls the maximum amount of time the INTERCHANGE server process waits for DTL I/O completion before checking for requests from the NI. Values are as follows:

Default value | 70 milliseconds
Minimum value | 5 milliseconds
Maximum value | 1,000 milliseconds

Generally, the smaller the cycle time, the faster the server will respond to the NI requests. If the cycle time is too small, however, the server will consume CPU time checking for requests.

### 2.3.5.4 ILAN$DTL_DWNL_FLAGS

The ILAN$DTL_DWNL_FLAGS parameter sets the default behavior of the download function. This default behavior may be overridden by using /QUALIFIER option on the download command. The flags specified in a download command are logically ORed with those specified by ILAN$DTL_DWNL_FLAGS.

The default value for ILAN$DTL_DWNL_FLAGS is MATCH. This flag requires that the device type, series, and revision match that of the file being downloaded. For more information on valid download flags that can be used for this parameter, refer to Table 3-8.

### 2.3.5.5 ILAN$DTL_MAX_ELEMENTS

The ILAN$DTL_MAX_ELEMENTS parameter controls the maximum number of elements the INTERCHANGE server process can define; that is, the expected number of outstanding solicited requests and the number of unsolicited requests combined. Values are as follows:

Default value | 500 elements
Minimum value | 50 elements
Maximum value | 100,000 elements

The value of ILAN$DTL_MAX_ELEMENTS must be greater than the value of ILAN$DTL_MAX_UNSOL_ELEMENTS. Note that ILAN$DTL_MAX_ELEMENTS only affects the number of points that can be defined as unsolicited and simultaneous pending data reads/writes. The parameter does not affect the number of physical points that can be defined on a BASEstar Classic system.

### 2.3.5.6 ILAN$DTL_MAX_UNSOL_ELEMENTS

The ILAN$DTL_MAX_UNSOL_ELEMENTS parameter controls the maximum number of elements that can be defined as unsolicited phypoints. This number is deducted from the value of ILAN$DTL_MAX_ELEMENTS. Values are as follows:

Default value | 50 phypoints
Minimum value | 50 phypoints
Maximum value | 10,000 phypoints

The value of ILAN$DTL_MAX_UNSOL_ELEMENTS must be less than ILAN$DTL_MAX_ELEMENTS.

### 2.3.5.7 ILAN$DTL_SCMP_FLAGS

The ILAN$DTL_SCMP_FLAGS parameter sets the default behavior of the simple file compare function.

The default value for ILAN$DTL_SCMP_FLAGS is ALL,NODATATABLES,NOREVISION. This value will have the compare operation check everything except the data tables and the PLC revision. For more information on valid simple file compare flags which may be used for this parameter, refer to Table 3-12.

### 2.3.5.8 ILAN$DTL_TIMEOUT

The ILAN$DTL_TIMEOUT parameter determines the timeout value for all DTL I/O calls. Values are as follows:

Default value | 1,000 milliseconds
Minimum value | 1,000 milliseconds
Maximum value | 600,000 milliseconds

The value of ILAN$DTL_TIMEOUT should be less than the shortest /TIMEOUT of the INTERCHANGE DAS device definitions. The desired behavior is to have the internal INTERCHANGE DTL call timeout before the BASEstar Classic device connect management request. If the BASEstar Classic request times out first, a cancellation request is attempted and any requests completion is ignored. Because INTERCHANGE does not support cancellation of requests, the actual INTERCHANGE DTL request may have successfully completed, yet give the incorrect impression that the INTERCHANGE function was not completed.

### 2.3.5.9 ILAN$DTL_UDC_TIMEOUT

The ILAN$DTL_UDC_TIMEOUT parameter determines the timeout value for all INTERCHANGE upload, download and compare calls. Values are as follows:

Default value | 300000 milliseconds
Minimum value | 1000 milliseconds
Maximum value | 3600000 milliseconds

The value of ILAN$DTL_UDC_TIMEOUT should be less than the shortest /TIMEOUT of the INTERCHANGE DAS device definitions. The desired behavior is to have the internal INTERCHANGE DTL call timeout before the BASEstar Classic device connect management request. If the BASEstar Classic request times out first, a cancellation request is attempted and any requests completion is ignored. Because INTERCHANGE does not support cancellation of requests, the actual INTERCHANGE DTL request may have successfully completed, yet give the incorrect impression that the INTERCHANGE function was not completed.

### 2.3.5.10 ILAN$DTL_UPL_FLAGS

The ILAN$DTL_UPL_FLAGS parameter sets the default behavior of the upload function. This default behavior may be overridden by using /QUALIFIER option on the upload command. The flags specified in a upload command are logically ORed with those specified by ILAN$DTL_UPL_FLAGS.

The default value for ILAN$DTL_UPL_FLAGS is NORUNNING,NOFAULT, which requires that the device not be in RUN mode and that it not be faulted. For more information on valid upload flags which may be used for this parameter, refer to Table 3-9.

### 2.3.5.11 ILAN$DTL_DUP_EI_ID

The ILAN$DTL_DUP_EI_ID parameter allows the DAS to communicate to more than forty (40) Ethernet Interfaces. The maximum number of Ethernet Interface IDs is forty (40). This maximum is a limit imposed by INTERCHANGE software. The DAS will by default allocate a new Ethernet Interface ID whenever it communicates to a new Ethernet Interface. However, if this parameter is set to "1", then the DAS wil allocate up to forty (40) Ethernet Interfaces IDs per DTL server process, rather than using a total of forty (40) IDs for all DTL server processes.

If this parameter is set, then the DAS will create up to sixty-four (64) DTL server processes, with each process using Ethernet Interface IDs from 1-40. The number of DTL server processes can be tuned by explicitly specifying the server process to use when communicating to a particular Ethernet Interface. See Section 2.3.2.2 for details on configuring a path to explicitly specify the DTL server to use when communicating.

## 2.3.6 Setting the DTL Server Process Quotas

The DAS for AB INTERCHANGE software allows you to tune the values of process quotas for the DCM_DTL$SRV_X process. Process parameters are read from the file BCC$SYSDATA:DCM_DTL$SRV_QUOTAS.DAT when a new DCM_DTL$SRV process is created.

Process quotas may need to be tuned depending on the number of devices and points configured and the throughput rate of requests through the server. To adjust a quota for the server process do the following:

1. Provide DETACH priviledge to ILAN$DEVSRV by modifying the RUN command in BCC$SYSDATA:ILAN$SYSTEM_STARTUP.COM.
2. Edit the file BCC$SYSDATA:DCM_DTL$SRV_QUOTAS.DAT as follows:
   1. Un-comment the line corresponding to the quota to be adjusted by removing the "!" character.
   2. Modify the existing quota value. If a value does not exist, add it to the file, separating the quota name and value with a space.

The new quotas will be in effect the next time the server process is started up by the DAS for AB INTERCHANGE software. The DCM_DTL$SRV_STOP utility can be used to shutdown running server processes without shutting down BASEstar Classic DCM.

## 2.3.7 Setting Up Plant-Floor Equipment

To set up your plant-floor equipment, refer to the Allen-Bradley documentation for your specific device.

While setting up the plant-floor equipment, you should record the following information that will be required for setting up the BASEstar Classic path and device definitions:

- The Ethernet Address of the Ethernet Interface(s)
- The Data Highway addresses of remote PLC stations

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