MC51QE128 RAM Function alignment

キャンセル
次の結果を表示 
表示  限定  | 次の代わりに検索 
もしかして: 

MC51QE128 RAM Function alignment

705件の閲覧回数
JaseMachine
Contributor I

I debugged an issue related to a RAM function failing after seemingly unrelated changes caused the starting address of a block of RAM used to hold a function to shift. When the block was aligned to even bytes the function executed flawlessly, but starting at an odd location caused Illegal Address (or Illegal Opcode, I don't remember) resets. My question is why does 16-bit alignment work?

ラベル(1)
0 件の賞賛
返信
1 返信

589件の閲覧回数
J2MEJediMaster
Specialist I

I know that the 68K processors (from which the ColdFire is derived) required 16-bit alignment on the code. ColdFire has variable-length instructions, but they might require that a function start on an even address. I would check the reference manual for your particular processor as to alignment restrictions on the code.

 

---Tom

0 件の賞賛
返信