Time to finish the study and document the learning process.
no MCU used for this task, workaround is a cheap and easy NE555 timer IC.
everything of this work around is about Time Constant of RC circuit, many others and fellows had been doing same trick to achive the goal, we should not be the only one.
The summary, SAVRIN Speedometer has been used as specimen and free of charge. NE555 and the quick prototype was capable to drive such speedometer to over it’s full span, perhaps this is only time on this speedometer to spin 200km per hour and over after factory shipment, I could not see anywhere of speeding would be allowed.
Note to learning scripts is self-explainable, it is only one example of problem-to-solution, it was rough but it is working flawlessly.
SAVRIN 里程表實際驅動測試, 破表200kmh
練習用 PROTURES 作仿真, 結果可參考, 但是不能100%反映實際的線路, 確定原理是可行的.
練習的時候, 每段連線都需要逐一連結, 交接處有個黑點, 表示兩根線是相連的, 否則是不連接的.
初次學習用PROTURES, 7.4 SP3 版本, 算是成功.
youtube 有 tutorial, http://www.youtube.com/watch?v=yt7Bhhvo-hU