Difference between revisions of "IoTGateway/BSP/Android/Gettingstarted/How to use GPIO for rk"

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RSB-4680
 
RSB-4680
  
{| style="width:500px" cellspacing="1" cellpadding="1" border="1"
+
{| cellspacing="1" cellpadding="1" border="1"
 
|-
 
|-
 
| GPIO Number
 
| GPIO Number
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Export GPIO then you can use control GPIO from userr space through sysfs
 
Export GPIO then you can use control GPIO from userr space through sysfs
  
Export GPIO 27
+
Export GPIO0
<pre># echo 27 > /sys/class/gpio/export
+
<pre># echo 219 > /sys/class/gpio/export
 
</pre>
 
</pre>
  
 
Set GPIO direction to in/out
 
Set GPIO direction to in/out
<pre># echo "out" > /sys/class/gpio/gpio27/direction
+
<pre># echo "out" > /sys/class/gpio/gpio219/direction
 
</pre>
 
</pre>
  
 
Set GPIO value 0/1 if GPIO pin define is output
 
Set GPIO value 0/1 if GPIO pin define is output
<pre>#  echo 1 > /sys/class/gpio/gpio27/value
+
<pre>#  echo 1 > /sys/class/gpio/gpio219/value
 
</pre>
 
</pre>
  
Line 75: Line 75:
  
 
Note:You have to configure GPIO to input
 
Note:You have to configure GPIO to input
<pre>#  echo "rising" > /sys/class/gpio/gpio27/edge
+
<pre>#  echo "rising" > /sys/class/gpio/gpio219/edge
 
</pre>
 
</pre>
  
Line 83: Line 83:
 
*none: Disable interrupt on both edges
 
*none: Disable interrupt on both edges
  
Unexport GPIO 27
+
Unexport GPIO0
<pre># echo 27 > /sys/class/gpio/unexport
+
<pre># echo 219 > /sys/class/gpio/unexport
 
</pre>
 
</pre>
  
 
==== Test ====
 
==== Test ====
  
GPIO 27 and GPIO 29 are taken as an example:
+
GPIO 219 and GPIO 220 are taken as an example:
  
*Connect GPIO 27 and GPIO 29
+
*Connect GPIO 219 and GPIO 220
*Export GPIO 27 and GPIO 29
+
*Export GPIO 219 and GPIO 220
<pre># echo 27 /sys/class/gpio/export
+
<pre># echo 219 > /sys/class/gpio/export
# echo 29 /sys/class/gpio/export
+
# echo 220 > /sys/class/gpio/export
 
</pre>
 
</pre>
  
*Set GPIO 27 to output
+
*Set GPIO 219 to output
<pre># echo "out" > /sys/class/gpio/gpio27/direction
+
<pre># echo "out" > /sys/class/gpio/gpio219/direction
 
</pre>
 
</pre>
  
*Set GPIO 29 to input
+
*Set GPIO 220 to input
<pre># echo "in" > /sys/class/gpio/gpio29/direction
+
<pre># echo "in" > /sys/class/gpio/gpio220/direction
 
</pre>
 
</pre>
  
*Change GPIO 27 to 1 and read GPIO 29 value
+
*Change GPIO 219 to 1 and read GPIO 220 value
<pre># echo 1 > /sys/class/gpio/gpio27/value
+
<pre># echo 1 > /sys/class/gpio/gpio219/value
# cat /sys/class/gpio/gpio29/value
+
# cat /sys/class/gpio/gpio220/value
 
1
 
1
 
</pre>
 
</pre>
  
*Change GPIO 27 to 0 and read GPIO 29 value
+
*Change GPIO 219 to 0 and read GPIO 220 value
<pre># echo 0 > /sys/class/gpio/gpio27/value
+
<pre># echo 0 > /sys/class/gpio/gpio219/value
# cat /sys/class/gpio/gpio29/value
+
# cat /sys/class/gpio/gpio220/value
0
+
0</pre>
</pre>
 

Latest revision as of 03:29, 26 October 2021

Configuration/Test

Configuration

The RK3288 bank/bit notation for GPIOs must be formed as "GPIO<GPIO_bank>_<gpio_bit>" 

The numeric value of GPIO is calculated as follows:

32 x (gpio_bank) + gpio_bit - 8

Group GPIO0 only 24 gpios,So each GPIO Num subtracts 8.

gpio_bit : A0~A7 0-7 B0~B7 8-15 C0~C7 16-23 D0~D7 24-31

E.g. GPIO2_A4 becomes 60

RSB-4680

GPIO Number GPIO formed Numeric Representation
GPIO0 GPIO7_A3
219
GPIO1
GPIO7_A4
220
GPIO2
GPIO7_A5
221
GPIO3
GPIO7_C5
237
GPIO4
GPIO8_A2
250
GPIO5
GPIO8_A3
251
GPIO6
GPIO8_A0
248
GPIO7
GPIO8_A1
249

Test

Export GPIO then you can use control GPIO from userr space through sysfs

Export GPIO0

# echo 219 > /sys/class/gpio/export

Set GPIO direction to in/out

# echo "out" > /sys/class/gpio/gpio219/direction

Set GPIO value 0/1 if GPIO pin define is output

#  echo 1 > /sys/class/gpio/gpio219/value

Used as IRQ signal

Note:You have to configure GPIO to input

#  echo "rising" > /sys/class/gpio/gpio219/edge
  • rising: Trigger on rising edge
  • falling: Trigger on falling edge
  • both: Trigger on both edges
  • none: Disable interrupt on both edges

Unexport GPIO0

# echo 219 > /sys/class/gpio/unexport

Test

GPIO 219 and GPIO 220 are taken as an example:

  • Connect GPIO 219 and GPIO 220
  • Export GPIO 219 and GPIO 220
# echo 219 > /sys/class/gpio/export
# echo 220 > /sys/class/gpio/export
  • Set GPIO 219 to output
# echo "out" > /sys/class/gpio/gpio219/direction
  • Set GPIO 220 to input
# echo "in" > /sys/class/gpio/gpio220/direction
  • Change GPIO 219 to 1 and read GPIO 220 value
# echo 1 > /sys/class/gpio/gpio219/value
# cat /sys/class/gpio/gpio220/value
1
  • Change GPIO 219 to 0 and read GPIO 220 value
# echo 0 > /sys/class/gpio/gpio219/value
# cat /sys/class/gpio/gpio220/value
0