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. Some of the descriptions are a bit odd and terse as the source is from non-native English speakers. More verbosity and better descriptions will be added as time allows.

EC Command List

• 0x10 Read voltage (2 bytes)
• 0x11 Read current (2 bytes)
• 0x12 Read ACR (2 bytes)
• 0x13 Read battery 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
  • Bits 5-7 Not defined
• 0x16 Read Battery State of Charge (SOC) (1 byte)
• 0x17 Read Battery gas guage chip serial number (6 bytes)
• 0x18 Read Battery gas guage data
• 0x19 Read board id (1 byte)
• 0x1a Read SCI source (1 byte)
  • 0x01 Game button
  • 0x02 Battery Status Change. Generated for any of:
    • AC plugged/unplugged
    • Battery inserted/removed
    • Battery Low
    • Battery full
    • Battery destroy
  • 0x04 Battery SOC Change
  • 0x08 Battery subsystem error
  • 0x10 Ebook mode change
  • 0x20?? Lid status change
• 0x1b Game key status (2 bytes) 9 bits of key status. 1 indicates key is depressed.
  • Bit 1: KEY_LR_R
  • Bit 2: KEY_RT_R
  • Bit 3: KEY_UP_L
  • Bit 4: KEY_DN_L
  • Bit 5: KEY_LF_L
  • Bit 6: KEY_RT_L
  • Bit 7: KEY_COLOR/MONO
  • Bit 8: KEY_UP_R
  • Bit 9: KEY_DN_R
• 0x1c Read SCI mask (1 byte)
• 0x1d Write SCI mask (1 byte)
• 0x1e Set date (day/mon/year)
  • Need details for using this.
• 0x1f Read battery subsystem error code (1 byte)
  • 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
  • 0x10 ACR fail (NiMH)
• 0x23 Set WLAN Power on/off
• 0x24 Wake up WLAN
• 0x25 WLAN reset
• 0x26 DCON power enable/disable
• 0x27?? Read power rail status
  • DCON status
  • WLAN status

EC IO Pinout

• Pin 6: GPIO00 VR_ON#
• Pin 9: GPIO01 WLAN_EN
• Pin 10: GPIO02 SWI#
• Pin 23: GPIO06 TX
• Pin 24: GPIO07 RX/BAT_L0
• Pin 25: GPIO08 EC_EAPD
• Pin 26: GPIO09 LED_PWR#
• Pin 27: GPIO0A LED_CHG_R#
• Pin 28: GPIO0B WAKEUP
• Pin 29: GPIO0C PWR_BUT#
• Pin 31: GPIO0E CHG
• Pin 32: GPIO0F CC0

• Pin 37: GPIO10 EC->WLAN Wakeup
  • Fix schematic!!

• Pin 1: GPIOE0 EC_WP#
• Pin 2: GPIOE1 CV_SET
• Pin 3: GPIOE2 DQ
• Pin 4: GPIOE3 LED_CHG_G
• Pin 33: GPIOE8 BAT_L1

• Pin

Firmware Address Map

0x00000 - 0ffff EC
0x10000 - dffff OFW
0xe0000 - ef7ff Reserved
0xef800 - effff Manufacturing data
0xf0000 - fffff Early startup code