Renesas Technology, M3T-PD45, Tool News, 20011016

MAEC TOOL NEWS: MAECT-M3T-PD45-011016D

M3T-PD45 Precaution

Please take note of the following problem in using emulator debugger (with an assembler) M3T-PD45 for the 4500 series MCUs.

Versions Concerned
M3T-PD45 V.1.10 Release 1 -- V.1.31 Release 1
Description
ASM45 may fail to optimize the description that contains a branch-optimizing instruction "BRN" and result in an out-of-range error.
2.1 Conditions
This problem may occur if the following two conditions are satisfied:
(1) The label used as the operand of a "BRN" instruction is forward referencing.
(2) The label in (1) above is described in the next page to the one where the "BRN" instruction has been described.
Note that the problem will not arise when the operand of the "BRN" instruction is either an immediate address or a backward-referencing label.

2.2 Example
```
------------------------------------------------------------------
   .org 0h,7bh
        BRN  lab1  ; <-- Processed as a "B" instruction, resulting 
                         in an error
        BRN  lab2
        BRN  lab3
  lab1: nop        ; A forward-referencing label
  lab2: nop
  lab3:
------------------------------------------------------------------
```
Workaround
Change the "BRN" instruction in the line where an error will appear to the "BL" instruction (jump to an address out of the page).
Schedule of Fixing the Problem
We plan to fix this problem in our next release.