Keyboard matrix
(r by c)
Peripheral ICs
Device
General-purpose
interface
gpio_[191:160]
pop_tq_temp_sense_ft
(POP side)
SDRAM
(package on package)
Temperature warning
SDRAM
(on the board)
Temperature warning
gpif-002
pop_tq_temp_sense_ft
(board side)
gpio_[159:128]
gpio_[127:96]
gpio_[95:64]
gpio_[63:34]
gpio_[31:0]
Public Version
General-Purpose Interface Environment
www.ti.com
25.2 General-Purpose Interface Environment
The general-purpose interface combines six GPIO modules for a flexible, user-programmable, GPIO
controller. The general-purpose interface implements functions that are not implemented with the
dedicated controllers in the device and require simple input and/or output software-controlled signals. The
general-purpose interface allows a variety of custom connections and expands the I/O capabilities of the
system to the real world.
shows a typical application using the general-purpose interface.
Figure 25-2. General-Purpose Interface Typical Application System Overview
NOTE:
Temperature Sensing
Most memories provide a temperature sensor to control the auto-refresh duty cycle. The
device monitors the temperature of the external memory using the pop_tq_temp_sense_ft
ball and a GPIO input. To do this, pop_tq_temp_sense_ft is connected to a GPIO through
the customer board. This feature is application-dependent.
CAUTION
Due to buffer strength, an external serial resistor must be connected to the
balls corresponding to gpio_120 to gpio_129 pads.
GPIO multiplexed on these pads should only be used with special electrical
attention, and if no other solutions are possible for their considered application.
They are not multiplexed on standard 1.8-V I/O cell buffers but specific dual
-voltage USIM/MMC-compliant buffers with nonstandard voltage domains,
power-up sequences, power states, and controls/configurations.
The general-purpose interface can physically connect the device to a keyboard matrix and peripheral
integrated circuits (ICs).
25.2.1 GPIO as a Keyboard Interface
The general-purpose interface can be used as a keyboard interface. You can dedicate channels based on
the keyboard matrix size (r x c).
shows row channels configured as inputs with the input
debounce feature enabled. The row channels are driven high with an external pullup. Column channels
are configured as outputs and drive a low-level.
3466
General-Purpose Interface
SWPU177N – December 2009 – Revised November 2010
Copyright © 2009–2010, Texas Instruments Incorporated
Содержание OMAP36 Series
Страница 174: ...174 List of Tables SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 692: ...692 MPU Subsystem SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 1084: ...1084 IVA2 2 Subsystem SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 1990: ...1990 2D 3D Graphics Accelerator SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2334: ...2334 Memory Subsystem SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2700: ...2700 Memory Management Units SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2868: ...2868 HDQ 1 Wire SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2974: ...2974 UART IrDA CIR SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3054: ...3054 Multichannel SPI SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3462: ...3462 MMC SD SDIO Card Interface SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3508: ...3508 General Purpose Interface SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3584: ...3584 Initialization SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3648: ...3648 Debug and Emulation SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...