Bool Read from R Register Always Returns False on Panasonic FP-XH PLC

[SeanJayZeng]

❗️Bool Read from R Register Always Returns False on Panasonic FP-XH PLC

🐞 Bug Description

When reading the boolean value of address R99A from a Panasonic FP-XH C30T/C40T/C60T PLC using the following code, the result is always false, even though the actual value in the PLC is true. The write operation is successful, and the value is confirmed as true in the PLC using Panasonic's software.

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✅ Verified Behavior

// Write boolean true to R99A - write succeeds
var writeResult = tcpNet.Register.Bool("R99A")
    .WriteAsync(bool.Parse("true"))
    .GetAwaiter().GetResult();
// writeResult.IsSuccess == true

// Read boolean from R99A - returns false, but actual PLC value is true
var data3 = Mewtocol.Ethernet(device.Ip, device.Port)
    .Build()
    .Register.Bool("R99A")
    .ReadAsync()
    .GetAwaiter()
    .GetResult();

// data3 == false, but actual bit in PLC is true

[fzred]

@SeanJayZeng HI, I have the same problem. Do you have a solution?

[Sandoun]

I will investigate this issue whenever i have some spare time. This project was part of a project i did at my old employer. I still have access to a panasonic plc but no longer to a license for fpwinpro, that makes further development kind of quirky.