USBTMC: Update test python code to use the new pyvisa namespace, and other misc fixes

Author: pigrew

examples/device/usbtmc/visaQuery.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-import visa
+import pyvisa
 import time
 import sys
 
@@ -54,9 +54,9 @@ def test_srq():
 	assert (inst.read_stb() == 0)
 	inst.write("123")
 
-	#inst.enable_event(visa.constants.VI_EVENT_SERVICE_REQ, visa.constants.VI_QUEUE)
-	#waitrsp = inst.wait_on_event(visa.constants.VI_EVENT_SERVICE_REQ, 5000)
-	#inst.discard_events(visa.constants.VI_EVENT_SERVICE_REQ, visa.constants.VI_QUEUE)
+	#inst.enable_event(pyvisa.constants.VI_EVENT_SERVICE_REQ, pyvisa.constants.VI_QUEUE)
+	#waitrsp = inst.wait_on_event(pyvisa.constants.VI_EVENT_SERVICE_REQ, 5000)
+	#inst.discard_events(pyvisa.constants.VI_EVENT_SERVICE_REQ, pyvisa.constants.VI_QUEUE)
 	#inst.wait_for_srq()
 	time.sleep(0.3)
 	stb = inst.read_stb()
@@ -77,8 +77,8 @@ def test_read_timeout():
 	t0 = time.monotonic()
 	try:
 		rsp = inst.read()
-		assert(false), "Read should have resulted in timeout"
-	except visa.VisaIOError:
+		assert(False), "Read should have resulted in timeout"
+	except pyvisa.VisaIOError:
 		print("  Got expected exception")
 	t = time.monotonic() - t0
 	assert ((t*1000.0) > (inst.timeout - 300))
@@ -99,23 +99,27 @@ def test_abort_in():
 	t0 = time.monotonic()
 	try:
 		rsp = inst.read()
-		assert(false), "Read should have resulted in timeout"
-	except visa.VisaIOError:
+		assert(False), "Read should have resulted in timeout"
+	except pyvisa.VisaIOError:
 		print("  Got expected exception")
 	t = time.monotonic() - t0
 	assert ((t*1000.0) > (inst.timeout - 300))
 	assert ((t*1000.0) < (inst.timeout + 300))
 	print(f"  Delay was {t:0.3}")
-	# Response is still in queue, so send a clear (to be more helpful to the next test)
+	# Response is still in queue, so read it out (to be more helpful to the next test)
 	inst.timeout = 800
 	y = inst.read()
 	assert(y == "xxx\r\n")
 
 def test_indicate():
 	# perform indicator pulse
-	usb_iface = inst.get_visa_attribute(visa.constants.VI_ATTR_USB_INTFC_NUM)
+	usb_iface = inst.get_visa_attribute(pyvisa.constants.VI_ATTR_USB_INTFC_NUM)
 	retv = inst.control_in(request_type_bitmap_field=0xA1, request_id=64, request_value=0x0000, index=usb_iface, length=0x0001)
-	assert((retv[1] == visa.constants.StatusCode(0)) and (retv[0] == b'\x01')), f"indicator pulse failed: retv={retv}"
+	# pyvisa used to return (statuscode,bytes), but now only returns bytes, so we need to handle both cases
+	if(isinstance(retv,bytes)):
+		assert(retv == b'\x01')
+	else:
+		assert((retv[1] == pyvisa.constants.StatusCode(0)) and (retv[0] == b'\x01')), f"indicator pulse failed: retv={retv}"
 
 
 def test_multi_read():
@@ -131,19 +135,19 @@ def test_multi_read():
 	#inst.chunk_size = old_chunk_size
 
 def test_stall_ep0():
-	usb_iface = inst.get_visa_attribute(visa.constants.VI_ATTR_USB_INTFC_NUM)
+	usb_iface = inst.get_visa_attribute(pyvisa.constants.VI_ATTR_USB_INTFC_NUM)
 	inst.read_stb()
 	# This is an invalid request, should create stall.
 	try:
 		retv = inst.control_in(request_type_bitmap_field=0xA1, request_id=60, request_value=0x0000, index=usb_iface, length=0x0001)
-		assert false
-	except visa.VisaIOError:
+		assert(False)
+	except pyvisa.VisaIOError:
 		pass
 
 	assert (inst.read_stb() == 0)
 
 
-rm = visa.ResourceManager()
+rm = pyvisa.ResourceManager()
 reslist = rm.list_resources("USB?::?*::INSTR")
 print(reslist)
 
@@ -167,7 +171,6 @@ def test_stall_ep0():
 print("+ multi read")
 test_multi_read()
 
-
 print("+ echo delay=0")
 inst.write("delay 0")
 test_echo(1,175)