1769-ASCII question

I am trying to get a 1769-ASCII module to trigger a scanner, the scanner requires me to send it a code which contains the hex value: 80. This value however is bigger than a SINT which is what the module wants to send. Is there a way to change the module to send INTs instead of SINT?

Since ASCII represents 127 different character codes, it is more than covered by 8 bits. Anything code at 128 (Hex 80) or beyond indicates extension of ASCII. I am not familiar with that module, just a general comment about ASCII.

80 would be 128 decimal...a SINT can hold 0-255...am i missing something?

I also wanted to ask if you are using this module with a Micrologix or Compactlogix?

What Make and Model of Scanner are you talking about?

Can you Post a link to the Manual?

ASCII is by nature an 8 Bit Code, thus the use of a SINT for it. So I think this might just be a misunderstanding.

Stu....

In a ControlLogix/CompactLogix system, all of the integer datatypes are signed, so the range of a SINT is -128 to +127.

Hex 0x80 = 128 decimal = 1000 0000 binary = "-128" in RSLogix 5000.

Yeah, that's what I thought. I can trigger it when directly sending the command via my PC serial port but It wasn't working from the PLC. I did notice when I was converting my tag values from hex to decimal in the tag database that they were different to the PC values. Thought there might be a different way of configuring the module itself.

I am using CompactLogix and a Sick IDM140-201D. We aren't using this model of scanner, I was just curious to see if I could get it going. Thanks for the quick replies.