i’m tring to get an RTC working on the BeagleV board
have added
&i2c2 {
clock-frequency = <100000>;
status = "okay";
extrtc: ds1307@68 {
compatible = "maxim,ds1307";
reg = <0x68>;
};
};
to light-beagle-ref.dts (changed clock from 400K to 100K JIC)
have verified that it is being compiled into light-beagle.dtb by converting the dtb to a dts
dmesg has
rtc-ds1307: probe of 2-0068 failed with error -121
have attached oscilloscope probes to both SCL and SDA, no signals at all
i2cdetect does not indicate there is a device present and there is no oscilloscope signal when running the command.
The connections: P9 row 1, gnd, row 2, 3v3, row 10 outside, SCL, row 10 inside SDA
P9 row 1 is closes to the barrel connector
what have i missed??
thanks,
edit #1
reconfigured I2C2 pins as led gpios, and i can toggle them. so hardware should be good.
edit #2
bada bing bada boom,
i2c2 is now working
my changes were to configure I2C2 in u-boot,
in light.c file,
thead-build/light-fm/tmp-glibc/work/light_beagle-oe-linux/u-boot/1_2020.10-r0/git/board/thead/light-c910/light.c
Around line 1856, comment out original I2C2 light_pin_mux and light_pin_cfg and add new light_pin_cfg as follows
/* P9_19 (Ball:G4) I2C2_SCL_MUX*/
//light_pin_mux(I2C2_SCL,3);
//light_pin_cfg(I2C2_SCL, PIN_SPEED_NORMAL, PIN_PN, 2);
light_pin_cfg(I2C2_SCL,PIN_SPEED_NORMAL,PIN_PN,4);
/* P9_20 (Ball:G3) I2C2_SDA_MUX*/
//light_pin_mux(I2C2_SDA,3);
//light_pin_cfg(I2C2_SDA, PIN_SPEED_NORMAL, PIN_PN, 2);
light_pin_cfg(I2C2_SDA, PIN_SPEED_NORMAL, PIN_PN, 4);
rebuild u-boot and yocto image and deploy to BeagleV board