[PIC] DSPIC33fj_Understanding disassembly Hex to assembly.

[IANZACH]

Could someone possibly help me understand how to disassemble hex code to assembly for a dspic33fj.

from what I understand the hex code is intel inhx32 format.

so i took a snippet of hex code and tried to decode it via a excel spreadsheet.

here's where i cannot get to the same code as mikro C dissasembly.

According to inhx32 The basic format of the HEX file is:
:BBAAAATTHHHH...HHHHCC.

where: BB is a two digit hex byte count reperesenting the number of data bytes appearing on the line. (I understand this )
AAAA is the hexadecimal address this has to be divided by two ( this i compute and is the same as Mikro C).

TT: is the record type ( this I also get the same as Mikro C)

HHHH... . HHHH: . HHHH . is a four-digit hexadecimal data word. The
format is low byte, followed by high byte. There
will be BB/2 data words following TT. this is where I come unstuck.

let say we have the following:

:100714000F832000F07F240020A0B70010002000E9

this would then equate to :

10 Bytes appearing on the line

Address line :0714 divded by 2 = 38A for pic

I now have 20 83 0F this is the same as mikro C

from what I gather I now have to change the hex (20) into Bin this gives me b=" 10000".
if I now reference table 7.1 of the DSPIC reference manual it refers to the Instruction MOV
this is also confirmed by Mikro C disassembly.

from here on I cant seem to work out the rest .we have 83 0F left.

according to Mikro C

MOV #2096, W15

according to Mikro C W15 register is hex 1E .
yet I cannot find this info anywhere and more over I cannot seem to calculate where Mikro c gets 2096 and W15 out of 83 0F

Can someone point me in the right direction.

 

[FvM]

Why don't you import the hex code in MPLAB and display it in code memory disassembly view?

 

[IANZACH]

I am trying to understand how the assembler works

 

[IANZACH]

So I have worked on it some more and found that by multiplying OF x 2 we get 1E which happens to be where register W15 sits.

Still trying to figure out where the #2096 comes from.

 

[IANZACH]

Ok I have worked out the way it works

Thanks guys for all the help