McQuay Micro Tech Open Protocol Driver Manual | Page 29 of 35 |
Appendix A.5. Advanced Map Descriptor Example 1– Reading direct address.
This example reads 10 data elements from a McQuay device starting at address 4096 (= 0x1000). The 10 values obtained are stored in DA_CHILLER1 starting at offset zero.
Map_Descriptor_Name | ,Data_Array_Name | ,Data_Array_Offset | ,Node_Name | ,Address | ,Length | ,Scan_Interval | ,Function | |
Chiller1_emulation | ,DA_CHILLER1 | ,0 |
| ,Chiller1 | ,4096 | ,10 | ,1.0s | ,Rdbc |
A data format of |
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Appendix A.6. Advanced Map Descriptor Example 2 – Controlling Bytes per Field – Reading
This example reads a McQuay device starting at address 4096 (= 0x1000) to 4099 incl. Before storing the data from the responses, the FieldServer combines the 4 values into a single value and stores this single value in a single Data Array element.
The driver reads address 4096 and gets a value. Call this value v0. The driver reads address 4097 and gets a value. Call this value v1. The driver reads address 4098 and gets a value. Call this value v2. The driver reads address 4099 and gets a value. Call this value v3.
When the 4th address has bee read, the driver calculates Total_Value = v0 + v1 * 0x100 + v2 * 0x10000 + v3 * 0x1000000. The Total_Value is stored in the Data Array.
Map_Descriptor_Name | ,Data_Array_Name | ,Data_Array_Offset | ,Node_Name | ,Address | ,Length | ,Bytes_per_Field | ,Scan_Interval | ,Function |
Chiller1_emulation | ,DA_CHILLER1 | ,0 | ,Chiller1 | ,4096 | ,1 | ,4 | ,1.0s | ,Rdbc |
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A value between 1 and 4 - tells the driver how many consecutive addresses to read from the remote device. The data value for each address is combined into a single value before it is stored.
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