I don't immediately recall, and I'm not in the office today to check.Question 1: where is top of the display; DSI connector on the panel pointing upwards (that's what it looks in the drawing as well as in real life)?
Just want to make sure because that DUT has seen some 'tweaking' and want to make sure I'm not hunting ghosts.
Correct. The MCU holds the GT911 in reset until the kernel drivers probe it.question 2: When looking at I2C-10 on a CM4, without starting the drivers (loading any V2 related overlay) I see below devicesCode:
pi@2GB-CM4:~ $ i2cdetect -li2c-0i2c i2c-22-mux (chan_id 0) I2C adapteri2c-10i2c i2c-22-mux (chan_id 1) I2C adapteri2c-20i2c fef04500.i2c I2C adapteri2c-21i2c fef09500.i2c I2C adapteri2c-22i2c bcm2835 (i2c@7e205000) I2C adapterpi@2GB-CM4:~ $ sudo i2cdetect -y 10 0 1 2 3 4 5 6 7 8 9 a b c d e f00: -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- 45 -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- 65 -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- --
device@0x45 is the MCU on the V2 displays, device@0x65 is unknown, no touchcontroller device will show up (GT911 is expected either on 0x14 or 0x5D) -> might not be powered up by the MCU when no driver is started.
Crypto chip, only used during autodetection.loading the overlay (dtoverlay=vc4-kms-dsi-ili9881-5inch) let's the touch controller show up, but still there is one device address unclaimed by the kernel and not known.--> what is device at address 0x65?Code:
pi@2GB-CM4:~ $ sudo i2cdetect -y 10 0 1 2 3 4 5 6 7 8 9 a b c d e f00: -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- UU -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- UU -- -- 60: -- -- -- -- -- 65 -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- --
Statistics: Posted by 6by9 — Fri Aug 22, 2025 2:17 pm