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doc:hardware:port.gpio
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doc:hardware:port.gpio [2017/08/16 14:37]
danitool [Finding GPIO pins (input) on the PCB]
doc:hardware:port.gpio [2017/09/17 15:54]
Lin-Buo-Ren [Hardware] Fix typoes
Line 8: Line 8:
  
 ===== Hardware ===== ===== Hardware =====
-GPIOs are commonly used in router devices for buttons or leds. They only safely supply or sink (pull to GND) a maximum of 4mA aprox., and the voltage is usually 3.3V when active. Only two states are posible: high or low. Depending on how a device is activated by a GPIO, active low or active high is defined.+GPIOs are commonly used in router devices for buttons or leds. They only safely supply or sink (pull to GND) a maximum of 4mA approx., and the voltage is usually 3.3V when active. Only two states are possible: high or low. Depending on how a device is activated by a GPIO, active low or active high is defined.
  
   * **Active high**: the device is activated when the GPIO is HIGH   * **Active high**: the device is activated when the GPIO is HIGH
Line 204: Line 204:
 GPIOmin=`expr $1 + $GPIOBASE` GPIOmin=`expr $1 + $GPIOBASE`
 GPIOmax=`expr $2 + $GPIOBASE` GPIOmax=`expr $2 + $GPIOBASE`
-nums=`seq $GPIOmin $GPIOmax` ​ 
  
 cd /​sys/​class/​gpio cd /​sys/​class/​gpio
doc/hardware/port.gpio.txt · Last modified: 2017/09/18 18:43 by tmomas