Differences
This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
en:c2_hardware_irq [2016/04/26 11:26] charles.park [Usage] |
en:c2_hardware_irq [2017/03/08 08:00] (current) odroid [Hardware GPIO-IRQ] |
||
---|---|---|---|
Line 3: | Line 3: | ||
**ODROID-C2** supports the GPIO interrupt of Edge trigger.\\ | **ODROID-C2** supports the GPIO interrupt of Edge trigger.\\ | ||
The maximum number of interrupt is limited to 8 when you use the falling(Low) or rising(High) edge trigger.\\ | The maximum number of interrupt is limited to 8 when you use the falling(Low) or rising(High) edge trigger.\\ | ||
- | If you use the Both (rising and falling together) edge triggers, the maximum number is only 4. | + | If you use the Both (rising and falling together) edge triggers, the maximum number is only 4. \\ |
- | You must use the **Linux 3.14.29-56 Apr** or higher to use the GPIO interrupt in the user-land. | + | Please note that SD card driver is using 2 interrupts to implement the card detection (insertion/remove) by default.\\ |
+ | So __**we can use only GPIO 6 IRQs**__. \\ | ||
+ | If you use an eMMC without SD card, you can access full 8 GPIO IRQs once you [[http://forum.odroid.com/viewtopic.php?f=136&t=26055&p=182162#p182037|disable the SD functionality]]. | ||
+ | |||
+ | You must use the **Linux Kernel 3.14.29-56 Apr** or higher to use the GPIO interrupt in the user-land. | ||
===== Usage ===== | ===== Usage ===== | ||
Line 14: | Line 18: | ||
=== GPIO Export === | === GPIO Export === | ||
- | echo [GPIO Number(Refer **[[en:c2_hardware|Expansion Connectors]]** )] > /sys/class/gpio/export | + | echo [GPIO Number(Refer **[[en:c2_hardware#expansion_connectors]]** )] > /sys/class/gpio/export |
- | e.g) GPIOX.BIT21 Export (Header Pin Number 7) | + | e.g) GPIOX.BIT21 Export (Pin Number 7) |
<code> | <code> | ||
Line 33: | Line 37: | ||
== Run == | == Run == | ||
+ | |||
+ | "Usage: aml_gpio_irq [GPIO Number]" | ||
<code> | <code> | ||
- | sudo aml_gpio_irq_test [GPIO Number] | + | sudo aml_gpio_irq_test 249 |
</code> | </code> | ||
Line 288: | Line 294: | ||
+ | |||
+ | ===== Kernel driver GPIO IRQ Example code by crashoverride ===== | ||
+ | |||
+ | [[http://forum.odroid.com/viewtopic.php?f=112&t=18559|HC-SR04 kernel driver]] | ||