# Serial and GPIOs on A1300 Slate Plus **URL:** \ **Category:** Router\ **Created:** [July 6, 2023, 3:46pm UTC](https://forum.gl-inet.com/t/serial-and-gpios-on-a1300-slate-plus/31150 "2023-07-06T15:46:46Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![dxf](https://forum-assets.gl-inet.com/letter_avatar_proxy/v4/letter/d/41988e/32.png) [@dxf](https://forum.gl-inet.com/u/dxf)\ **Post date:** [July 7, 2023, 3:13am UTC](https://forum.gl-inet.com/t/serial-and-gpios-on-a1300-slate-plus/31150/2 "2023-07-07T03:13:13Z")
For first question: The i2c is used to control the ET6326 to realize the breathing function of the led. which is implemented in /usr/bin/gl\_i2c\_led and you can refer to this link to learn about its implementation. > [@GL-MT1300 LED control instructions](https://forum.gl-inet.com/t/gl-mt1300-led-control-instructions/13338): > > #stop glinet control /etc/init.d/led stop /etc/init.d/led disable #reset I2C IC echo 0 \> /sys/class/leds/gl-mt1300:blue/brightness echo 0 \> /sys/class/leds/gl-mt1300:white/brightness i2cset -f -y 0 0x30 0x00 0x1F i2cset -f -y 0 0x30 0x00 0x1A #adjust brightness i2cset -f -y 0 0x30 0x06 0x3f #blue 0x3f \* 0.125mA = 8mA i2cset -f -y 0 0x30 0x07 0x7f #white 0x7f \* 0.125mA = 16mA #light up LED i2cset -f -y 0 0x30 0x04 0x01 i2cset -f -y 0 0x30 0x04 0x04 #put out LED i2cset -f -… For second question: I think you need to modify the driver to implement it, or you can refer to this patch? I think you should also encounter other difficulties, if you realize, I hope you can share with me. [https://github.com/gl-inet/gl-infra-builder/blob/main/patches-mt798x-7.6.6.1/3008-support-uart1-no-use-cts-and-rts.patch](https://github.com/gl-inet/gl-infra-builder/blob/main/patches-mt798x-7.6.6.1/3008-support-uart1-no-use-cts-and-rts.patch) --- _[View the full topic](https://forum.gl-inet.com/t/serial-and-gpios-on-a1300-slate-plus/31150)._