DEC may work or not, depending how your terminal will send your data. If he send CR+LF, this will screw your data for sure.

i've tried with
Code:
Command     var byte
SerialByte  var byte

hserout ["---- Ready ----",13,10]
Start:
        while 1
            if pir1.5 then
                hserin 10,jump,[Command, DEC3 SerialByte]
                gosub ManageBytes
                endif
            Jump:
            wend
        goto start

ManageBytes:
        hserout ["Command=",Command,_
                 "   SerialByte=", #SerialByte,13,10,13,10]
        return
And it's working just fine, with terminators (CR+LF) or not

depending of your Baudrate, 3.58 MHz may work fine or not. Worth to use the PicMultiCalc to see the error %