Ec specification

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Operational Specification of the XO embedded controller (EC)

These pages will eventually document the commands and responsibilities of the EC in the XO system. Currently its not much more than a cut and paste from a variety of emails, trac tickets, and operational info extracted from the way the EC is known to work. It will be expanded as time allows.

EC Commands

• 0x10 Read voltage (2 bytes)
• 0x11 Read current (2 bytes)
• 0x12 Read ACR (2 bytes)
• 0x13 Read bat temperature (2 bytes)
• 0x14 Read ambient temperature (2 bytes)
• 0x15 Read battery status (1 byte)
  • Bit 0: 1: battery exists
  • Bit 1: 1: battery full charged
  • Bit 2: 1: battery low

        Bit 3: // 1: battery destroys                                                            

        Bit 4: // 1: AC in                                                                      

    g. 0x16 // Read SOC          (1 byte)                                              

    h. 0x17  // Read gas guage chip serial number (6 bytes)                                          

    i. 0x18   // Read gas guage data                                                                  

    j. 0x19   // Read board id    (1 byte)                                              

    k. 0x1a  // Read SCI source       (1 byte)                                              

        The SCI source will keep what the SCI event when a SCI happens.                        

        SCI_WACKUP_EVENT           0x01       // Game button                                          

       SCI_BATTERY_STATUS_CHANGE      0x02       // AC plugged/unplugged, Battery inserted/remove,  

                                               // Battery Low, Battery full, Battery destorys          

        SCI_SOC_CHANGE                0x04       // SOC Change                                         

        SCI_ABNORMAL_EVENT               0x08       // Battery Abnormal                                  

        SCI_EB_MODE_CHANGE             0x10        // EB_MODE changes                             

    l. 0x1b   // Game key status        (2 bytes)                                            

        It will return 2 bytes key status (only 9 bits used). The bits define as following.       

        If game pad pushed the bit will set to 1.                                              

        Bit 9: KEY_DN_R, Bit 8: KEY_UP_R, Bit 7:KEY_COLOR/MONO                                  

        Bit 6: KEY_RT_L, Bit 5: KEY_LF_L, Bit 4:KEY_DN_L,                                            

        Bit 3: KEY_UP_L, Bit 2: KEY_RT_R, Bit 1:KEY_LR_R                                            

    m. 0x1c // Read SCI mask         (1 byte)                                              

    o. 0x1d // Write SCI mask  (1 byte)                                              

    p. 0x1e // Set date (day/mon/year)                                                       

    q. 0x1f   // Read Abnormal code        (1 byte)                                              

        There are abnormal codes define as following:                                                 

        0x02 - Pack info fail                          LiFePO4 & NiMH                             

        0x04 - Over voltage checking fail         LiFePO4                                           

        0x05 - Over temperature (58C)                LiFePO4                                           

        0x06 - Gauge stop or sensor break!!   LiFePO4 & NiMH                             

        0x07 - Sensor out of control             NiMH                                         

        0x09 - Battery ID fail & temperature > 52C    Unknown ID                            

        0x10 - ACR fail                               NiMH                                       

    r. 0x23  // Set WLAN Power on/off                                                       

    s. 0x24  // Wake up WLAN                                                                    

    t. 0x25   // WLAN reset                                                                           

    u. 0x26  // DCON power enable/disable