Yesterday, I decided to layout the common signals for my UARTS, the timer and the PPI chips. This entailed the data base, reset, some address lines, the I/O read/write and the data bus. While I was routing the I/O ~RD line the trace would not connect to the correct the PPI 8255 pin. After zooming in I saw that the 8255 was labeled I/O ~WR instead. So I figured I made the symbol wrong. Yet the schematic has it correct Pin t is I/O RD and pin 36 is I/O WR. So I went back into my custom library and checked it out a completely as I could. Checked each pin and ran the Check for Duplicate and Off grid pins, that was OK. I then remade the Net List and checked the IO.NET file. Here Pin 5 is I/O~RD and Pin 36 is I/O~WR which is correct. I also checked to see if the 8255 was listed twice, figuring that maybe a later one had it wrong, but no soap. Then in PcbNew I deleted my old 8255 from the layout, then updated the PCB only to find that pins 5 and 36 are swapped again. In the dialog box shown when the update is done says that Pin 5 is connected to I/O ~WR and Pin 36 is connected to I/O ~RD, which is wrong. I struggled with this most of the yesterday and have not had any luck repairing this. Does anyone have an idea of how to fix this? Thanks Mike.
post your files 
OK, I’m still new at this what files would you like to see? Mike
at a minimum, your .lib and .kicad_mod. best just zip your whole project directory.
I hope this is what you are looking for. Please remember I’m a novice at this and it maybe a little messy. Thanks Mike
IO.zip (348.1 KB)
Thank you. Sometimes I can look right at something and not see it. My wife tells me that when I’m looking in the refrigerator most every day. Getting old I spect. Mike
Sometimes I see what I expect to see instead of what is there. 
I think you are correct in saying that. Many times I have in my mind exactly what something looks like, but it’s not the same anymore. I can remember things from 60 years ago, better than something I did yesterday. Well… I swapped the NETS and it work perfectly. Thanks a million. Mike
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