Experimental Physics and
Industrial Control System

Mark Rivers via Tech-talk <tech-talk at aps.anl.gov> · Fri, 10 Apr 2020 16:44:22 +0000

Hi Will,

I don't know the state of Kunal's repository that you referenced.  I think the more "official" simulated motor repository is this one:

https://github.com/epics-motor/motorMotorSim

There are actually 2 drivers in that source code, a "Model 2" driver (drvMotorSim.c) and a new "Model 3" driver (motorSimDriver.cpp).  I recommend only using motorSimDriver.cpp since that is the current standard framework.

The example IOC loads 8 motors.  The first 4 are the old Model 2 driver, and the last 4 are the new Model 3 driver.

I just tested homing with both drivers.

With the Model 2 driver when the homing is complete MSTA is 0xa.  This is bits 1 and 3 which mean

        unsigned int RA_HOME        :1; /* The home signal is on */
        unsigned int RA_DONE        :1; /* a motion is complete */

With the Model 3 driver when the homing is complete the MSTA is 0x82.  This is bits 1 and 7 which mean
        unsigned int EA_HOME        :1; /* encoder home signal on */
        unsigned int RA_DONE        :1; /* a motion is complete */

So one driver sets RA_HOME (not encoder home) while the other set EA_HOME (encoder home).

Note that neither of them set bit 14 which is
  unsigned int RA_HOMED       :1; /* Axis has been homed.*/

This is probably an bug in these drivers, they should be setting that bit as well.

Mark

________________________________
From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of William Cork via Tech-talk <tech-talk at aps.anl.gov>
Sent: Friday, April 10, 2020 10:25 AM
To: tech-talk at aps.anl.gov
Subject: Home motorSim Device

Playing around with the motor and asyn modules to get more familiar with EPICS motion control.

I'm using an example motorSim found here: https://github.com/shroffk/motorsim.git
Using:
asyn-R4-37
motor-R7-1
calc-R3-7-3

Having an issue where I tell an sioc using motorSim to home but, the MSTA record never updates the HOMED bit.

Startup deck has these lines to configure motorSim device:
```
motorSimCreate( 0, 0, -32000, 32000, 0, 1, 6 )
drvAsynMotorConfigure("motorSim1", "motorSim", 0, 6)
```

fakemotor.db:
```
record(ao, "$(Sys)$(Dev)-SP") {
    field(FLNK, "$(Sys)$(Dev)-SP_")
}

record(seq, "$(Sys)$(Dev)-SP_") {
    #disable mtr rec processing
    field(DOL1, "1")
    field(LNK1, "$(Mtr).DISA")

    # write setpoint to mtr rec
    field(DLY2, "0.1")
    field(DOL2, "$(Sys)$(Dev)-SP")
    field(LNK2, "$(Mtr).VAL CP")

    # to re-enable mtr rec processing, write or process "$(Sys)$(Dev)Cmd:Go-Cmd"
}

record(ai, "$(Sys)$(Dev)-I") {
    field(INP, "$(Mtr).RBV CPP")
}

record(bo, "$(Sys)$(Dev)Cmd:Go-Cmd") {
    field(DOL, "0")
    field(OUT, "$(Mtr).DISA CPP")
}

record(bo, "$(Sys)$(Dev)Cmd:Stop-Cmd") {
    field(VAL, "1")
    field(OUT, "$(Mtr).STOP CPP")
}

record(bi, "$(Sys)$(Dev)Sts:Moving-Sts") {
    field(INP, "$(Mtr).DMOV CPP")
    field(ZNAM, "Moving")
    field(ONAM, "Done")
}
```

Does motorSim have support for homing?
Is it broken from the seq record in fakemotor.db?

Your help is appreciated,
Will

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System