Generic A32/D32 VME Device Support

Author: Ned D. Arnold (1997)

Table of contents

This device support module provides generic access to any VME register in the A32/D32 address space. It supports ai, ao, bi, bo, longin, longout, mbbi, and mbbo record types. Arbitrary bit fields within 32-bit registers can be read and written using the PARM field to specify the starting bit and width.

Configuration

Call devA32VmeConfig in the IOC startup script before iocInit:

devA32VmeConfig(card, a32base, nreg, iVector, iLevel)
Argument Description
card Card number (0-3)
a32base Base address of card in A32 VME space (max 0xf0000000)
nreg Number of 32-bit registers on this card (max 64)
iVector Interrupt vector (MRD100 only; use 0 for no interrupts)
iLevel Interrupt level (MRD100 only)

Example:

devA32VmeConfig(0, 0x80000000, 44, 0x3e, 5)
dbLoadRecords("$(VME)/vmeApp/Db/VME_DAC.db", "P=$(PREFIX),D=1,N=chan1,DTYP=Generic A32 VME,C=0,S=0,H=10,L=-10")

The VME_DAC.db template provides a rate-of-change-limited DAC output with tweaking and can be used with this device support by setting DTYP="Generic A32 VME".

Supported Record Types

All record types use DTYP "Generic A32 VME" with VME_IO link type.

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

Where:

  • card is the card number configured by devA32VmeConfig
  • register is the register offset (0, 1, 2, …) – not a byte address
  • parm specifies the bit field of interest (format varies by record type)

PARM Field Formats

Record Type PARM Format Description
ai, ao lsb, width, type lsb=starting bit (0-31), width=number of bits, type=0 for unipolar, 1 for bipolar (2’s complement)
bi, bo bit Single bit number (0-31)
longin, longout lsb, width lsb=starting bit, width=number of bits
mbbi, mbbo lsb, width lsb=starting bit, width=number of bits

Examples 

# Read bits 0-15 of register 5 on card 0 as an analog input (unipolar)
record(ai, "$(P)reading") {
    field(DTYP, "Generic A32 VME")
    field(INP,  "#C0 S5 @0,16,0")
}

# Write to bit 3 of register 10 on card 0
record(bo, "$(P)control") {
    field(DTYP, "Generic A32 VME")
    field(OUT,  "#C0 S10 @3")
}

Debug Variable 

var devA32VmeDebug 0
Level Output
0 No messages
>= 5 Hardware initialization information
>= 10 Record initialization information
>= 15 Write commands
>= 20 Read commands