Re: Re: Re: How to set bo PV to zero when starting Modbus IOC

[高振华 via Tech-talk <tech-talk at aps.anl.gov>]

Hi Mark,
I see,thank you very much.

Best regards.
Gao Zhenhua

> -----原始邮件-----
> 发件人: "Mark Rivers" <rivers at cars.uchicago.edu>
> 发送时间: 2021-05-25 20:12:19 (星期二)
> 收件人: "高振华" <gaozh at ihep.ac.cn>
> 抄送: "tech-talk at aps.anl.gov" <tech-talk at aps.anl.gov>
> 主题: Re: Re: How to set bo PV to zero when starting Modbus IOC
> 
>  Hi Zhenhua,
> 
> > 1. Is the Dbpf command placed after iocInit written to the PLC after the IOC is started and before the scanner mechanism starts scanning processing?
> 
> 
> No, dbpf  happens after iocInit is complete and scanning has started.
> 
> 
> However, if you use autosave and PINI=YES then it does happen as part of iocInit, before scanning starts.
> 
> >  2. Is it performed as the first write to the PLC with the start of the IOC?
> 
> 
> The dbpf will be the first write to that PLC register if you set PINI=NO on the record that writes to that register.  If other records have PINI=YES then it will not be the first write to the PLC, just the first write to that register.
> 
> 
> Mark
> 
> 
> 
> ________________________________
> From: 高振华 <gaozh at ihep.ac.cn>
> Sent: Tuesday, May 25, 2021 2:26 AM
> To: Mark Rivers
> Cc: tech-talk at aps.anl.gov
> Subject: Re: Re: How to set bo PV to zero when starting Modbus IOC
> 
> Hi Mark,
> Thanks,two questions remain:
>  1. Is the Dbpf command placed after iocInit written to the PLC after the IOC is started and before the scanner
>     mechanism starts scanning processing?
>  2. Is it performed as the first write to the PLC with the start of the IOC?
> 
> Best regards.
> Gao Zhenhua
> 
> 
> > -----原始邮件-----
> > 发件人: "Mark Rivers" <rivers at cars.uchicago.edu>
> > 发送时间: 2021-05-25 09:00:06 (星期二)
> > 收件人: "高振华" <gaozh at ihep.ac.cn>
> > 抄送: "tech-talk at aps.anl.gov" <tech-talk at aps.anl.gov>
> > 主题: Re: How to set bo PV to zero when starting Modbus IOC
> >
> > Hi Zhenhua,
> >
> > The value in the database file will be replaced by the value read from the device.
> >
> > There are 2 ways to force the value to zero when the IOC start up:
> >
> > - Add the PV to autosave and set the value to 0 before the IOC reboots. The value in autosave will be written to the device if PINI=1.
> > - Put a dbpf command after iocInit which writes zero to the PV.
> >
> > Mark
> >
> >
> > Sent from my iPhone
> >
> > > On May 24, 2021, at 7:39 PM, 高振华 <gaozh at ihep.ac.cn> wrote:
> > >
> > > Hi Mark,
> > > I tried to set BO PV to zero when starting Modbus R2-11 IOC, but failed. PINI worked, but VAL didn't work.When IOC is started, what is written to PLC is the value that has just been read.
> > > Can't the Modbus R2-11 driver set BO PV to zero when IOC starts?
> > >
> > > Best regards.
> > > Gao Zhenhua
> > >
> > > --
> > > BSRF(Beijing Synchrotron Radiation Facility)
> > > Email:gaozh at ihep.ac.cn
> > >
> > >
> > >
> 
> 
> --
> 
> 祝好！
> 高振华
> 
> 
> 电话：010-88235426
> Email:gaozh at ihep.ac.cn
> 
> 


--
      
祝好！
高振华


电话：010-88235426
Email:gaozh at ihep.ac.cn