On Wednesday, August 29, 2012 4:09:49 PM UTC-4, Dennis Lee Bieber wrote:
>
> Don't the commands require an <esc> character? "\x1BA" (or
> "\x1B\x41")
>
> OTOH, if the <esc> is issued behind the scenes,
I'm not sure which esc char it is asking for, I don't think libusb is providing
its own, and it seems like the one you suggested isn't what it wants either..
> ... and you do not need to issue some sort of read()
> the "2" you are seeing is the "number of bytes written";
>
> you need to issue a read request to retrieve the returned printer
>
> status.
>
You are correct about the 2 being the number of bytes written. However when I
issue a read command I get:
>>> ep.write('\x1BA')
4
>>> ep.read(1)
Traceback (most recent call last):
File "<pyshell#75>", line 1, in <module>
ep.read(1)
File "C:\Python32\lib\site-packages\usb\core.py", line 301, in read
return self.device.read(self.bEndpointAddress, size, self.interface,
timeout)
File "C:\Python32\lib\site-packages\usb\core.py", line 654, in read
self.__get_timeout(timeout)
File "C:\Python32\lib\site-packages\usb\backend\libusb01.py", line 483, in
bulk_read
timeout)
File "C:\Python32\lib\site-packages\usb\backend\libusb01.py", line 568, in
__read
timeout
File "C:\Python32\lib\site-packages\usb\backend\libusb01.py", line 384, in
_check
raise USBError(errmsg, ret)
usb.core.USBError: [Errno None] b'libusb0-dll:err [_usb_setup_async] invalid
endpoint 0x02\n'
Avoiding the read command all together I should be able to write "<esc> E" and
have it feed some paper, which it is not doing, so obviously there is more to
uncover. That said I feel this endeavor has evolved and is no longer pertinent
to the Python group so I will let you guys off the hook on this (although
responses/suggestions are still welcome).
Thanks for all your help!
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