From 018547cdf305cc8011f8addaf62175bea2e29e18 Mon Sep 17 00:00:00 2001
From: zimoch <zimoch>
Date: Tue, 18 Aug 2015 14:28:26 +0000
Subject: [PATCH] allow and document direct conversion from VAL/OVAL to integer
 to get more bits on 64 bit systems

---
 doc/ai.html       |  6 ++++++
 doc/ao.html       |  6 ++++++
 src/devaoStream.c | 13 +++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/doc/ai.html b/doc/ai.html
index 47bd975..96383a4 100644
--- a/doc/ai.html
+++ b/doc/ai.html
@@ -41,6 +41,12 @@ written or read value.
    (=20.0/0xFFFF) maps 0x0000 to -10.0, 0x7FFF to 0.0 and 0xFFFF to 10.0.
    Using unsigned formats with values &ge; 0x800000 gives different results
    on 64 bit machines.
+   <p class="new">
+   If <code>LINR=="NO CONVERSION"</code> (the default), <code>VAL</code>
+   is directly converted from and to <code>long</code> without going through
+   <code>RVAL</code>. This allows for more bits on 64 bit machines.
+   To get the old behavior, use <code>LINR=="LINEAR"</code>.
+   </p>
   </dd>
  <dt>ENUM format (e.g. <code>%{</code>):</dt>
   <dd>
diff --git a/doc/ao.html b/doc/ao.html
index 8c0d7c7..b505dea 100644
--- a/doc/ao.html
+++ b/doc/ao.html
@@ -40,6 +40,12 @@ written or read value.
    (=20.0/0xFFFF) maps -10.0 to 0x0000, 0.0 to 0x7FFF and 10.0 to 0xFFFF.
    Using unsigned formats with values &ge; 0x800000 gives different results
    on 64 bit machines.
+   <p class="new">
+   If <code>LINR=="NO CONVERSION"</code> (the default), <code>OVAL</code>
+   is directly converted to <code>long</code> without going through
+   <code>RVAL</code>. This allows for more bits on 64 bit machines.
+   To get the old behavior, use <code>LINR=="LINEAR"</code>.
+   </p>
   </dd>
  <dt>ENUM format (e.g. <code>%{</code>):</dt>
   <dd>
diff --git a/src/devaoStream.c b/src/devaoStream.c
index 929d728..fb643dc 100644
--- a/src/devaoStream.c
+++ b/src/devaoStream.c
@@ -20,6 +20,7 @@
 
 #include "devStream.h"
 #include <aoRecord.h>
+#include <menuConvert.h>
 #include <epicsExport.h>
 
 static long readData (dbCommon *record, format_t *format)
@@ -42,6 +43,11 @@ static long readData (dbCommon *record, format_t *format)
             if (streamScanf (record, format, &rval)) return ERROR;
             ao->rbv = rval;
             if (INIT_RUN) ao->rval = rval;
+            if (ao->linr == menuConvertNO_CONVERSION)
+            {
+                ao->val = (double) rval;
+                return DO_NOT_CONVERT;
+            }
             return OK;
         }
     }
@@ -65,6 +71,13 @@ static long writeData (dbCommon *record, format_t *format)
         }
         case DBF_LONG:
         {
+            if (ao->linr == menuConvertNO_CONVERSION)
+            {
+                long val;
+                if (INIT_RUN) val = (long) ao->val;
+                else val = (long) ao->oval;
+                return streamPrintf (record, format, val);
+            }
             return streamPrintf (record, format, (long) ao->rval);
         }
     }