AnsweredAssumed Answered

Issues(?) with command ADDW and SUBW on STM8S105C6

Question asked by berton.ivan.001 on Jul 3, 2018

Hi

I use STM8S-Discovery Board with STM8S105C6 and ST Visual Develop v4.3.10, Windows 10.

 

If I use command ADDW or SUBW this way:

------------------------------------------------------------------------------

Example 1


                  ldw           X,#400         ;Load 400 into X


                  addw       X,#100          ;Add direct 100 to word X


test            cpw         X,#500          ;Compare X with 500
                   jreq         test               ;Jump to "test" if X=500

------------------------------------------------------------------------------

it works properly. The content X is 500.

 

But if I do this

------------------------------------------------------------------------------

Example 2

 

k                equ           $0365        ;RAM register is called k


                  mov          k,#100       ;Move 100 into k
                  ldw           X,#400       ;Load 400 into X


                  addw        X,k             ;Add k to word X


test            cpw         X,#500        ;Compare X with 500
                   jreq         test             ;Jump to "test" if X=500

------------------------------------------------------------------------------

it doesn´t work. The content of X is not 500.

SUBW behave the same way.

 

According the programming manual PM004 Doc ID 13590 Rev3, page 78 and 152,

Example 2 should actually work. Issue or do I miss something?

 

Thanks for reply.

Ivan 

Outcomes