Closedown

script/local.py

@@ -90,6 +90,61 @@ def trig_scienta():
         Scienta.waitReady(-1)
         Scienta.waitNewImage(3000, image_id)
 
+KEI_SAMPLE = "X03DA-KEITHLEY-1:"
+KEI_REF = "X03DA-KEITHLEY-2:"
+
+def init_keithley(dwell):
+    """
+    prepare keithleys for gpib polling:
+    passive, bus triggered, dwell time
+    
+    dwell = dwell time in seconds (0.1 - 20.0)
+    """
+    caput(KEI_SAMPLE + "READSCAN.SCAN", 0)
+    caput(KEI_SAMPLE + "TTYPE", 2)
+    caput(KEI_REF + "READSCAN.SCAN", 0)
+    caput(KEI_REF + "TTYPE", 2)
+    nplc = 5.
+    navg = dwell / 0.1
+    if navg > 100:
+        nplc *= 2
+        navg /= 2
+    navg = min(navg, 100)
+    nplc = min(nplc, 10.)
+    caput(KEI_SAMPLE + "NPLC", nplc)
+    caput(KEI_REF + "NPLC", nplc)
+    caput(KEI_SAMPLE + "NAVG", navg)
+    caput(KEI_REF + "NAVG", navg)
+
+def read_keithley():
+    """
+    trigger keithleys, wait until done, and read the result into EPICS.
+    the value can then be read by pshell from the channel.
+    """
+    dwell1 = caget(KEI_SAMPLE + "TOTTIME") / 1000.
+    dwell2 = caget(KEI_REF + "TOTTIME") / 1000.
+    dwell = max(dwell1, dwell2)
+    caput(KEI_SAMPLE + "DOINIT", 1)
+    caput(KEI_REF + "DOINIT", 1)
+    caput(KEI_SAMPLE + "DOTRIGGER", 1)
+    caput(KEI_REF + "DOTRIGGER", 1)
+    time.sleep(dwell)
+    caput(KEI_SAMPLE + "DOFETCH", 1)
+    caput(KEI_REF + "DOFETCH", 1)
+
+def free_keithley():
+    """
+    switch keithleys to free run.
+    0.1 s polling and dwell time
+    """
+    caput(KEI_SAMPLE + "NPLC", 5.)
+    caput(KEI_REF + "NPLC", 5.)
+    caput(KEI_SAMPLE + "NAVG", 1)
+    caput(KEI_REF + "NAVG", 1)
+    caput(KEI_SAMPLE + "READSCAN.SCAN", 9)
+    caput(KEI_REF + "READSCAN.SCAN", 9)
+    caput(KEI_SAMPLE + "TTYPE", 0)
+    caput(KEI_REF + "TTYPE", 0)
 
 diag_channels = []
 diag_channels.append(Scienta.channelBegin)       #diag_channels.append(ChannelDouble("ChannelBegin", "X03DA-SCIENTA:cam1:CHANNEL_BEGIN_RBV"))