INTRODUCTION

The purpose of this application note is to demonstrate how KEELOQ? code hopping technology can be conveniently employed to implement an automatic code hopping password generator/keypad.

Using a PIC12C508, the hopping code produced by an HCS300 is converted to a string of 16 hex digits. This string is then transferred to the PC via the keyboard line, thereby emulating the actual pressure of a sequence of keys on a standard PC/AT? keyboard. Since this conversion process is transparent to any application, it appears as if the user is simply typing on a PC/AT-type keyboard.

PIC12C508屬于集成電路（IC） > 微控制器。微芯科技股份有限公司制造生產(chǎn)的PIC12C508微控制器微控制器產(chǎn)品是相對復雜的用戶可編程數(shù)字邏輯器件。這些產(chǎn)品與視為微控制器的器件密切相關(guān)，兩者之間的區(qū)別主要體現(xiàn)在制造商選擇的用詞。不過按照傳統(tǒng)，微控制器集成了工作存儲器，也更可能包含混合信號外設，并且往往與更簡單的軟件范例結(jié)合使用，旨在重復執(zhí)行一系列預定義的任務。