Experimental Physics and
Industrial Control System

Mark Rivers <[email protected]> · Mon, 14 Dec 2015 19:28:14 +0000

Please send the output of

dbpr Iso:GantryCouch:Collimator:Actual 10

Mark


Sent from my iPhone

> On Dec 14, 2015, at 11:22 AM, "[email protected]" <[email protected]> wrote:
> 
> 
> 
> I did the experiment Mark suggested and found that drvModbusAsyn.c is working as
> expected - it returns small negative integers when small negative voltages are applied to the converter.  BUT in those cases RVAL is still reported as a large positive integer.  Details follow:
> 
>> On Sat, 12 Dec 2015, Mark Rivers wrote:
>> 
>> You could add the following printf statement to drvModbusAsyn.c::readPlcInt and see what the output is for that value.
>> 
>>       case dataTypeInt16:
>>       result = (epicsInt16)value;
>> printf("readPlcInt, offset=%d, value=0x%x, result=%d (0x%x)\n", offset, value, result, result);
>>       break;
> 
> I did that and got these results.  When Vin is a small positive value +0.002 V,
> value is a small positive integer and RVAL is a small positive integer:
> 
> readPlcInt, offset=0, value=0x1, result=1 (0x1)
> 
> dbgf Iso:GantryCouch:Collimator:Actual.RVAL
> DBR_LONG:           6         0x6
> 
> (the voltage varies slightly between the printf and dbgf outputs)
> 
> But when Vin is -0.008 V, value is a small negative integer BUT RVAL is a large positive integer:
> 
> readPlcInt, offset=0, value=0xfff4, result=-12 (0xfffffff4)
> 
> dbgf Iso:GantryCouch:Collimator:Actual.RVAL
> DBR_LONG:           65524     0xfff4
> 
> So it seems RVAL is handled differently than value.  Is there some way to make
> RVAL behave like value?
> 
> Jon Jacky
> 
> PS - here are answers to Mark's other questions about MODBUS_DATA and asynReport
> 
>> In your database for the ai record what is the drvInfo field in the INP link? Is it still MODBUS_DATA? If so, that should be fine.
> 
> Yes, dbpr reports the INP field is INP:INST_IO @asynMask(CollimCouch, 0, 16, 1000)MODBUS_DATA
> 
>> Please send the output of the following command:
>> 
>> asynReport(1, "CollimCouch")
> 
> I believe addr 0 is connected to Vin in the output shown above.
> 
> epics> asynReport(1, "CollimCouch")
> CollimCouch multiDevice:Yes canBlock:Yes autoConnect:Yes
>    enabled:Yes connected:Yes numberConnects 1
>    nDevices 6 nQueued 0 blocked:No
>    asynManagerLock:No synchronousLock:No
>    exceptionActive:No exceptionUsers 0 exceptionNotifys 0
>    traceMask:0x1 traceIOMask:0x0 traceInfoMask:0x1
>    addr 0 autoConnect Yes enabled Yes connected No exceptionActive No
>        exceptionActive No exceptionUsers 0 exceptionNotifys 0
>        blocked No
>        traceMask:0x1 traceIOMask:0x0 traceInfoMask:0x1
>    addr 5 autoConnect Yes enabled Yes connected No exceptionActive No
>        exceptionActive No exceptionUsers 0 exceptionNotifys 0
>        blocked No
>        traceMask:0x1 traceIOMask:0x0 traceInfoMask:0x1
>    addr 3 autoConnect Yes enabled Yes connected No exceptionActive No
>        exceptionActive No exceptionUsers 0 exceptionNotifys 0
>        blocked No
>        traceMask:0x1 traceIOMask:0x0 traceInfoMask:0x1
>    addr 4 autoConnect Yes enabled Yes connected No exceptionActive No
>        exceptionActive No exceptionUsers 0 exceptionNotifys 0
>        blocked No
>        traceMask:0x1 traceIOMask:0x0 traceInfoMask:0x1
>    addr 2 autoConnect Yes enabled Yes connected No exceptionActive No
>        exceptionActive No exceptionUsers 0 exceptionNotifys 0
>        blocked No
>        traceMask:0x1 traceIOMask:0x0 traceInfoMask:0x1
>    addr 1 autoConnect Yes enabled Yes connected No exceptionActive No
>        exceptionActive No exceptionUsers 0 exceptionNotifys 0
>        blocked No
>        traceMask:0x1 traceIOMask:0x0 traceInfoMask:0x1
> modbus port: CollimCouch
>    asynOctet server:   AcromagCollimCouch
>    modbusSlave:        0
>    modbusFunction:     4
>    modbusStartAddress: 00
>    modbusLength:       011
>    plcType:            AcromagXT1221
>    I/O errors:         0
>    Read OK:            2207
>    Write OK:           0
>    pollDelay:          0.100000
>    Time for last I/O   1 msec
>    Max. I/O time:      7 msec
>    Time per hist. bin: 1 msec
> 
> 
>

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System