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− | == The linux LED driver class ==
| + | #REDIRECT [[GPIO_LEDS]] |
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− | On recent kernel, linux have a led driver. This led can be driven from /sys/class/leds/ directory.
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− | For APF28Dev, the led is configurable under the directory :
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− | <pre class="apf">
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− | # cd /sys/class/leds/apfdev:green:user
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− | </pre>
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− | === Blinking ===
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− | The blinking style can be selected with ''trigger'' file. By defaut on APF28Dev, Heartbeat is selected :
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− | <pre class="apf">
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− | # cat /sys/class/leds/apfdev:green:user/trigger
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− | none nand-disk mmc0 timer [heartbeat] backlight gpio default-on
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− | </pre>
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− | Blinking style can be changed with ''echo'' command :
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− | <pre class="apf">
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− | # echo "nand-disk" > /sys/class/leds/apfdev:green:user/trigger
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− | # cat /sys/class/leds/apfdev:green:user/trigger
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− | none [nand-disk] mmc0 timer heartbeat backlight gpio default-on
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− | </pre>
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− | With this "nand-disk" option selected, the led will blink each time nand access occur (try with ''sync'' command to see it blinking).
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