Texas Instruments bq78350-R1, Техническое описание

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88 SLUUBD3D – September 2015 – Revised September 2018
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Host Controlled GPIO
Chapter 14
SLUUBD3D – September 2015 – Revised September 2018
Host Controlled GPIO
14.1 Introduction
The bq78350-R1 can have the SMBus host read or drive GPIO. Two of the available seven GPIO are
dedicated GPIO (GPIO A and GPIO B), and the other five are default configured as the LED display
(LED1...5). However, each LED pin can be individually selected to be read or driven by the host SMBus
as a GPIO.
14.2 Configuring the GPIO
Each pin chosen as a host controlled GPIO pin must be selected as a GPIO, even the dedicated ones, in
GPIO Config . Once selected, the Input or Output selection is set in GPIO Output Enable . If the
corresponding bit in GPIO Config is not set then the bit in GPIO Output Enable is ignored. If configured
as an output the default state upon reset of the device can be set through GPIO Output Default .
Additionally each pin can be configured as either Open Drain (OD) or as a 3-mA Current Sink (CS)
through the
GPIO Type settings.
Table 14-1. Host Controlled GPIO Enable Options
Class Subclass Name Format Min Max Default Unit
GPIO GPIO Config GPIO Config Hex 0x00 0xFE 0x00 —
7 6 5 4 3 2 1 0
GPIO B GPIO A LED5 LED4 LED3 LED2 LED1 RSVD
GPIO B (Bit 7) : GPIO B
1 = Active as GPIO
0 = Inactive
GPIO A (Bit 6) : GPIO A
1 = Active as GPIO
0 = Inactive
LED5 (Bit 5) : GPIO 5
1 = Active as GPIO
0 = Inactive (used as LED5)
LED4 (Bit 4) : GPIO 4
1 = Active as GPIO
0 = Inactive (used as LED4)
LED3 (Bit 3) : GPIO 3
1 = Active as GPIO
0 = Inactive (used as LED3)
LED2 (Bit 2) : GPIO 2
1 = Active as GPIO
0 = Inactive (used as LED2)