Difference between revisions of "IoTGateway/BSP/Android/Gettingstarted/How to use GPIO for rk"
From ESS-WIKI
Xingxing.li (talk | contribs) |
|||
(One intermediate revision by one other user not shown) | |||
Line 17: | Line 17: | ||
RSB-4680 | RSB-4680 | ||
− | {| | + | {| cellspacing="1" cellpadding="1" border="1" |
|- | |- | ||
| GPIO Number | | GPIO Number | ||
Line 60: | Line 60: | ||
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 | + | Export GPIO0 |
− | <pre># echo | + | <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/ | + | <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/ | + | <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/ | + | <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 | + | Unexport GPIO0 |
− | <pre># echo | + | <pre># echo 219 > /sys/class/gpio/unexport |
</pre> | </pre> | ||
==== Test ==== | ==== Test ==== | ||
− | GPIO | + | GPIO 219 and GPIO 220 are taken as an example: |
− | *Connect GPIO | + | *Connect GPIO 219 and GPIO 220 |
− | *Export GPIO | + | *Export GPIO 219 and GPIO 220 |
− | <pre># echo | + | <pre># echo 219 > /sys/class/gpio/export |
− | # echo | + | # echo 220 > /sys/class/gpio/export |
</pre> | </pre> | ||
− | *Set GPIO | + | *Set GPIO 219 to output |
− | <pre># echo "out" > /sys/class/gpio/ | + | <pre># echo "out" > /sys/class/gpio/gpio219/direction |
</pre> | </pre> | ||
− | *Set GPIO | + | *Set GPIO 220 to input |
− | <pre># echo "in" > /sys/class/gpio/ | + | <pre># echo "in" > /sys/class/gpio/gpio220/direction |
</pre> | </pre> | ||
− | *Change GPIO | + | *Change GPIO 219 to 1 and read GPIO 220 value |
− | <pre># echo 1 > /sys/class/gpio/ | + | <pre># echo 1 > /sys/class/gpio/gpio219/value |
− | # cat /sys/class/gpio/ | + | # cat /sys/class/gpio/gpio220/value |
1 | 1 | ||
</pre> | </pre> | ||
− | *Change GPIO | + | *Change GPIO 219 to 0 and read GPIO 220 value |
− | <pre># echo 0 > /sys/class/gpio/ | + | <pre># echo 0 > /sys/class/gpio/gpio219/value |
− | # cat /sys/class/gpio/ | + | # 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