板子上有一顆IC：MMA7660FC，我們來試着讀一下它的芯片手冊，當然讀的目的是爲了驅動它。這也是我們驅動開發的目的：拿過來一塊未知的IC，去讀它的芯片手冊，支持那種通訊協議，然後編碼讓它動起來。
he sensor has three power modes: Off Mode, Standby Mode, and Active Mode to offer the customer different power
consumption options. The sensor is only capable of running in one of these modes at a time.
支持三種模式：off mode，standby mode，active mode.
During the Active Mode, continuous measurement on all three axes is enabled. In addition, the user can choose to enable:Shake Detection, Tap Detection, Orientation Detection, and/or Auto-Wake/Sleep Feature and in this mode the digital analysis for any of these functions is done. The user can configure the samples per second to any of the following: 1 sample/second,2 samples/second, 4 samples/second, 8 samples/second, 16 samples/second, 32 samples/second, 64 samples/second, and 120 samples/second, for the Auto-Sleep state. If the user is configuring the Auto-Wake feature, the selectable ranges are:
1 sample/second, 8 samples/second, 16 samples/seconds and 32 samples/second. Depending on the samples per second selected the power consumption will vary.
在active mode下，3軸的連續測量是開啓的。用戶可選擇開啓：抖動檢測，敲擊檢測，方向檢測。或者 auto-wake auto sleep模式的切換。也可以配置每秒採樣的率.
採樣率配置：this can be configured in the SR (0x08) register.Once the user configurable samples per
second is chosen, the device will update the data for all 3 axes in the register at a resolution of 6-bits/axis
The user can choose to enable/disable any of the following interrupts in the INTSU (0x06) register: Front/Back Interrupt,
Up/Down/Left/Right Interrupt, Tap Detection Interrupt, GINT (real-time motion tracking), Shake on X-axis, Shake on Y-axis, and
Shake on Z-axis. If the GINT is enabled, real-time motion tracking can be configured to trigger an interrupt after every sensor data update
中斷的配置在 INTSU(0x06) 寄存器裏面.
寄存器相關：
slave addr:0x4c
write方式：
read方式：
相關的說明就這麼多，至於後面的編程實現，我們需要參考這邊的芯片手冊來實現。所以芯片手冊讀懂，讀通很重要。雖然很難讀，可是讀不懂沒辦法寫代碼。所以英文閱讀和理解能力一定要好。猜測能力也要好些，剩下的就是經驗和實驗了。任何驅動不可能一下子就明白它的實現原理並立即把它實現出來，大多的需要try。
關於這顆IC我們就先介紹到這裏.