MRD-100 Machine Status Link

Author: APS BCDA

Table of contents

The MRD-100 is a VMEbus Machine Status Link (MSL) module that provides real-time access to accelerator status data from the APS storage ring. The module is located in the A32/D32 VME address space and provides data including beam current, lifetime, BPM positions, insertion device status, front-end shutter states, and other beamline-relevant signals.

Configuration

An iocsh script is provided that handles configuration and database loading:

iocshLoad("$(VME)/iocsh/MSL_MRD100.iocsh", "PREFIX=xxx:, INSTANCE=msl:, VME=$(VME), ADDRESS=0xA0000200, INT_VEC=0xA0")
Macro Required Default Description
PREFIX Yes – IOC prefix
INSTANCE Yes – Instance prefix
ADDRESS Yes – A32 base address
INT_VEC Yes – Interrupt vector
VME Yes – Location of vme module
INT_LVL No 5 Interrupt level
CARD No 0 Card number
ID1 No $(INSTANCE) ID1 prefix
ID2 No $(INSTANCE)us ID2 prefix

The script calls devAvmeMRDConfig(base, vector, level) and loads msl_mrd100.db. For canted undulator beamlines, use MRD100_CantedID.db instead.

Only one instance of the MRD-100 is supported.

When configuring manually:

devAvmeMRDConfig(0xA0000200, 0xA0, 5)
dbLoadRecords("$(VME)/vmeApp/Db/msl_mrd100.db", "C=0,S=$(INSTANCE),ID1=$(INSTANCE),ID2=$(INSTANCE)us")

Supported Record Types

All use DTYP "MRD-100" with VME_IO link type.

field(INP, "#C<card> S<register> @<parm>")
field(OUT, "#C<card> S<register> @<parm>")

Where card is always 0 and register is the register number.

PARM Field Formats

Record Type PARM Format Description
ai s,w,t s=start bit, w=width, t=type (0=unipolar, 1=bipolar)
bi s s=bit number
bo s s=bit number
longin s,w s=start bit, w=width
mbbi s s=start bit

Debug Variable 

var devAvmeMRDDebug 0
Level Output
0 No messages
>= 5 Write command messages
>= 10 Read command messages