drvAscii codes

[Ian A Smith <ias@roe.ac.uk>]

I'm trying to get epics to talk to an (awkward) piece of equipment.  It 
requires: "[stx]command[etx][cr][lf]", where of course, [stx] and [etx] 
are ascii 2 and 3.

I've succeeded in puting the [etx] on the end of lines but I get the 
literal string "\002" instead of [stx] at the start, so I'm looking for 
help!

The record which successfully puts [etx] in line termination is:

record(stringout,"scu2CCS:shutter:coms:txCmd") {
    field(DESC,"string output record")
    field(SCAN,"Passive")
    field(PINI,"YES")
    field(PHAS,"0")
    field(EVNT,"0")
    field(DTYP,"Ascii SIO")
    field(DISV,"1")
    field(SDIS,"0.000000000000000e+00")
    field(DISS,"NO_ALARM")
    field(PRIO,"LOW")
    field(FLNK,"0.000000000000000e+00")
    field(VAL,"\003\r\n")
    field(DOL,"\003\r\n")
    field(OMSL,"closed_loop")
    field(OUT,"@/pty/shutterM <writeCmt %s>")
    field(SIOL,"0.000000000000000e+00")
    field(SIML,"0.000000000000000e+00")
    field(SIMS,"NO_ALARM")
    field(IVOA,"Continue normally")
    field(IVOV,"")
}

and the record which fails to put [stx] in the command line is:

record(stringin,"scu2CCS:shutter:test") {
    field(DESC,"string input record")
    field(SCAN,"10 second")
    field(PINI,"NO")
    field(PHAS,"0")
    field(EVNT,"0")
    field(DTYP,"Ascii SIO")
    field(DISV,"1")
    field(SDIS,"0.000000000000000e+00")
    field(DISS,"NO_ALARM")
    field(PRIO,"LOW")
    field(FLNK,"0.000000000000000e+00")
    field(VAL,"string")
    field(INP,"@/pty/shutterM <\002SUI><%s>")
    field(SIOL,"0.000000000000000e+00")
    field(SIML,"0.000000000000000e+00")
    field(SIMS,"NO_ALARM")
}

TIA
--
Ian A Smith               Telephone: +44 (0) 131 668 8255
Royal Observatory         Fax:       +44 (0) 131 668 8314
Blackford Hill            Web:       http://www.roe.ac.uk/
Edinburgh
EH9 3HJ
UK