#4 VI_ATTR_ASRL_END_OUT

[Larry C]

Have you had any requests for interface methods to VI_ATTR_ASRL_END_OUT ?
self.serial_end_out = keyw.get("serial_end_out", serial_end_output)
__get_end_output()
__set_end_output() indicates the method used to terminate read operations

I wanted to read the current value and didn't see a direct method for accomplishing that.
I hacked in my own patch in SerialInstrument() and it worked; but I'm curious about what other folks think of this idea.
Thanks; Larry

[Florian Bauer]

Hi Larry,

I recently took over PyVISA maintenance. If you have something working already, I'm glad to incorporate it into one of the next releases.
Can you provide a patch and a bit more info on what it accomplishes? Personally I'm not familiar with visa over serial.

Thanks,
Florian

[Larry C]

Hack from January, for serial_end_out

[Larry C]

Florian, I got your reply ... it has been a while since I looked at this, so I just uploaded what I have from January.

This is a unified diff versus the original visa.py file from package version 1.3.
Will upload it as well.

--- visa.py 2008-03-26 13:52:28.000000000 -0700
+++ visa_modified.py 2012-01-30 13:58:16.000000000 -0800
@@ -643,6 +643,7 @@
no_end_input = VI_ASRL_END_NONE
last_bit_end_input = VI_ASRL_END_LAST_BIT
term_chars_end_input = VI_ASRL_END_TERMCHAR
+serial_end_output = VI_ATTR_ASRL_END_OUT

# The following aliases are used for the "parity" property
no_parity = VI_ASRL_PAR_NONE
@@ -672,7 +673,7 @@
_warn_for_invalid_keyword_arguments(keyw,
("timeout", "term_chars", "chunk_size", "lock",
"delay", "send_end", "values_format",
- "baud_rate", "data_bits", "end_input", "parity", "stop_bits"))
+ "baud_rate", "data_bits", "end_input", "serial_end_out", "parity", "stop_bits"))
keyw.setdefault("term_chars", CR)
Instrument.__init__(self, resource_name,
**_filter_keyword_arguments(keyw,
@@ -686,6 +687,7 @@
self.stop_bits = keyw.get("stop_bits", 1)
self.parity = keyw.get("parity", no_parity)
self.end_input = keyw.get("end_input", term_chars_end_input)
+## self.serial_end_out = keyw.get("serial_end_out", serial_end_output)
def __get_baud_rate(self):
return vpp43.get_attribute(self.vi, VI_ATTR_ASRL_BAUD)
def __set_baud_rate(self, rate):
@@ -730,6 +732,13 @@
end_input = property(__get_end_input, __set_end_input, None,
"""indicates the method used to terminate read operations""")

+ def __get_end_output(self):
+ return vpp43.get_attribute(self.vi, VI_ATTR_ASRL_END_OUT)
+ def __set_end_output(self, serial_end_out):
+ vpp43.set_attribute(self.vi, VI_ATTR_ASRL_END_OUT, serial_end_out)
+ serial_end_out = property(__get_end_output, __set_end_output, None,
+ """indicates the method used to terminate serial write operations""")
+

class Interface(ResourceTemplate):
"""Base class for GPIB interfaces.

[Larry C]