手持抄表,4*4按键，通过按下相应按键完成相应抄表功能。-Hand-held meter, 4* 4 button, by pressing the appropriate button to complete the corresponding meter reading function.

北京振中手持抄表机，型号TP900抄表程序，实现红外抄表-Beijing vibration in the hand-held meter reading machine, Model TP900 meter reading procedures infrared meter reading

解释cortex-m3，比较不错 我在看了(This book is not all about the technical details of Cortex - M3. The utility model before chapters for Cortex - M3 The brick of hand, and also the value added reference material of CM3 processor. If you want to study further,