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Only for training and service purposes
LGE Internal Use Only
3. TECHNICAL BRIEF
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3.9.8. Mode Select and JTAG Interfaces
The mode pins to the MSM7227 device determine the overall operating mode of the ASIC. The options under the
control of the mode inputs are Native mode, which is the normal subscriber unit operation, ETM mode, which
enables the built-in trace mode, and test mode for factory testing. The MSM7227 device meets the intent of the
ANSI/IEEE 1149.1A-1993 feature list. The JTAG interface can be used to test digital interconnects between devices
within the mobile station during manufacture.
3.9.9. General-Purpose Input/Output Interface
The MSM7227 IC includes 133 general purpose input/output (GPIO) pins, and each can be configured as a digital
input or digital output. Inputs can be set to have a pull-up, pull-down, keeper, or no-pull. Output drive strength is
also programmable. Software assigns functions to the GPIOs and their configurations are set accordingly. Some of
the GPIO pins have alternate functions supported on them. The alternate functions include USB interface, additional
RAM, ROM, general-purpose chip selects, parallel LCD interface, and a UART interface. The function of these pins is
documented in the various software releases.
3.9.10. UART
The MSM7227 device employs three UARTs. UART1 has dedicated pins while UART2 and UART3 share multiplexed
pins.
UART1 for Bluetooth
UART2 for USIM interface
UART3 for data
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3.9.11. USB
The MSM7227 IC supports one High Speed USB (HS-USB) USBH port with built-in PHY and one Full Speed USB-UICC
port. The MSM7227 IC supports USB interfaces using two controllers:
The primary controller is the HS-USB port with an integrated physical layer (PHY). This HS
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-USB port is
also capable of supporting USB operations at low-speed and full-speed.
The secondary controller is the FS USB-UICC port, which only supports host mode functionality.