--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+(* ********************************************************************** *)
+(* Progetto FreeScale *)
+(* *)
+(* Sviluppato da: Ing. Cosimo Oliboni, oliboni@cs.unibo.it *)
+(* Sviluppo: 2008-2010 *)
+(* *)
+(* ********************************************************************** *)
+
+include "emulator/translation/translation.ma".
+
+(* errori possibili nel fetch OPCODE / ILLEGAL ADDRESS *)
+ninductive error_type : Type ≝
+ ILL_OP: error_type
+| ILL_FETCH_AD: error_type
+.
+
+(* - errore: interessa solo l'errore
+ - ok: interessa info, nuovo pc *)
+ninductive fetch_result (A:Type) : Type ≝
+ FetchERR : error_type → fetch_result A
+| FetchOK : A → word16 → fetch_result A.
+
+ndefinition fetch_byte_aux ≝
+λm:mcu_type.λcur_pc:word16.λbh:byte8.
+ match full_info_of_word16 m (Byte bh) with
+ [ None ⇒ FetchERR ? ILL_FETCH_AD
+ | Some info ⇒ FetchOK ? info cur_pc
+ ].
+
+ndefinition fetch_word_aux ≝
+λm:mcu_type.λcur_pc:word16.λw:word16.
+ match full_info_of_word16 m (Word w) with
+ [ None ⇒ FetchERR ? ILL_FETCH_AD
+ | Some info ⇒ FetchOK ? info cur_pc
+ ].