Two statements from assembly - trying to convert the code in PBasic Pro

[SteveB]

In PBP, the label "ISR" will be annotated in assembly as "_ISR" as a literal (i.e. constant). It represents the address of the first instruction following the label in PBP. The address is a 21 bit address. The bottom 8 bits (low byte, bits 0-7) are directly readable/writeable. The high byte (bits 8-15) and upper byte (bits 16-20) can only be read/written through the registers PCLATH and PCLATU respectively

So... You will likely see something like this as well:

movlw ((INTHAND) >> 16)
movwf PCLATU

movlw INTHAND
movwf PCL


When PCL is written to, the contents of PCLATH and PCLATU are written to the Program Counter along with the value to the PCL. This will cause the instruction found at that address to be the next instruction executed.

One other thing. Since INTHAND is a constant, ((INTHAND) >> 16) and ((INTHAND) >> 8) will be evaluated when the program is compiled. So, the actual assembly will only see an 8 bit value.