CA problem while using EVENT I/O

[Cheng Weixing <chengwx@ssrc.ac.cn>]

hello. I have developed the AVME9321 12 bit I/O card driver and it seems
work now.  But I can't display
the channel with MEDM and such tools. when using period scanning, it's
working well. I wonder if I set
the db file correctly.

the db file is like this:
record(ai, "$(user):aiAvme9321_Chan0")
{
 field(DESC, "Acromag AVME9321 Input")
 field(SCAN, "I/O Intr")
 field(DTYP, "acromagAVME")
 field(INP, "#C0 S0@")
 field(LINR, "LINEAR")
 field(EGUF, "10")
 field(EGUL, "-10")
 field(EGU, "Counts")
 field(HOPR, "4096")
 field(LOPR, "0")
 field(HIHI, "8")
 field(HIGH, "6")
 field(LOW, "4")
 field(LOLO, "2")
 field(HHSV, "MAJOR")
 field(HSV, "MINOR")
 field(LSV, "MINOR")
 field(LLSV, "MAJOR")
}

after loading my applications:
-> dbl
epics:aiAvme9321_Chan0
epics:aiExample
epics:aiExample1
epics:aiExample2
epics:aiExample3
epics:calcExample
epics:calcExample1
epics:calcExample2
epics:calcExample3
epics:xxxExample
value = 0 = 0x0
 ->dbgf "epics:aiAvme9321_Chan0"
DBR_DOUBLE:         0             /* it's always zero now, I havn't sent
any external trigger to I/O card*/
value = 0 = 0x0

Then when I send a trigger message. ( in my isr, there is a logMsg, so
there has a message on the screen)

-> interrupt: interrupt running now...the value is 54d0
/* it's okay, the isr is running well*/

-> dbgf "epics:aiAvme9321_Chan0"            /* no response for there
have no trigger now, not 0 */
(then I send a trigger )
interrupt: interrupt running now...the value is 5c10
DBR_DOUBLE:         -2.80586                   /* the channel value is
correct*/
value = 0 = 0x0

using dbgf I can get the channel value, but CA has some problems, I
can't using MEDM to monitor the
epics:aiAvme9321_Chan0 channel. even the epics:aiExample channel, I
can't monitor either.

I have set the environment varible EPICS_CA_ADDR_LIST correctly , and
when using periodic scanning,
these channels can all be monitored by MEDM.  what's wrong with it?

Any suggestion is great appreciated.

Cheng Weixing from SSRF