System variables - INTERBUS master
Available for AXC F x152
On INTERBUS master devices, three diagnostic registers map the diagnostic display to the control
system:
- diagnostic status registers
- diagnostic parameter registers
- extended diagnostic parameter registers
They inform the control system about the current state of the INTERBUS system. In the application program, operating states, errors, and other information appear as inputs.
Diagnostic status registers
Information on the operating state of the INTERBUS master is stored in the diagnostic status register. A specific INTERBUS master state is assigned to each bit in the diagnostic status register.
The following system variables can be used to read the diagnostic status register information.
Variables in the diagnostic status registers
| System variable | Type | Description |
| IB_DIAG_STATUS_REG_HI | BYTE | Master diagnostic status register, high byte |
| IB_DIAG_STATUS_REG_LOW | BYTE | Master diagnostic status register, low byte |
| IB_DIAG_STATUS_REG_SYSFAIL | BOOL | “System failure” error message |
| IB_DIAG_STATUS_REG_WARN | BOOL | Defined warning time exceeded |
| IB_DIAG_STATUS_REG_QUAL | BOOL | Defined error density exceeded |
| IB_DIAG_STATUS_REG_USER | BOOL | User error/parameterization error |
| IB_DIAG_STATUS_REG_PF | BOOL | Peripheral fault |
| IB_DIAG_STATUS_REG_BUS | BOOL | Bus error |
| IB_DIAG_STATUS_REG_CTRL | BOOL | INTERBUS master/hardware fault |
| IB_DIAG_STATUS_REG_DTC | BOOL | Diagnostic routine is active |
| IB_DIAG_STATUS_REG_RUN | BOOL | Data transmission is active |
| IB_DIAG_STATUS_REG_ACT | BOOL | Selected configuration is ready for operation |
| IB_DIAG_STATUS_REG_RDY | BOOL | The INTERBUS master is ready for operation |
Diagnostic parameter registers
The diagnostic parameter register provides additional information on an error indicated in the diagnostic status register and is rewritten whenever a malfunction occurs. If no malfunction has been detected, the diagnostic parameter register contains the value 0.
Exception: If an INTERBUS local bus error cannot be located then the value 128 is indicated in the diagnostic parameter register (i.e., bit 7 is set).
The location in the local bus structure and an error code is stored in the diagnostic parameter register for each error:
0A50hex
For each error code, there's a plain text description and hints to remedy the error, e.g. for the above "address overlap" error:
| Error code | Type | Description and remedy |
0A50hex |
BOOL | Error when assigning a process data item. Input or output address assigned more than once. Remedy:
|
Find all error codes and their descriptions in the INTERBUS Diagnostics Guide
user manual (Prod.-Id. 2747293, IBS SYS DIAG DSC UM E, and other languages - see Diagnostics - Local bus).
Variables in the diagnostic parameter registers
| System variable | Type | Description |
| IB_DIAG_PARAM_REG_HI | BYTE | Master diagnostic parameter register, high byte |
| IB_DIAG_PARAM_REG_LOW | BYTE | Master diagnostic parameter register, low byte |
| IB_DIAG_PARAM_2_REG_HI | BYTE | Extended master diagnostic parameter register, high byte |
| IB_DIAG_PARAM_2_REG_LOW | BYTE | Extended master diagnostic parameter register, low byte |
Extended diagnostic parameter registers
The extended diagnostic parameter register is only updated once the "Confirm_Diagnostics" service (0760hex) has been sent. By default, it is set in the MPM at address 37E6hex and can also be moved to the I/O area using the Set_Value service (Variable_ID 010Chex).