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by fuwen0202
Thu Jun 04, 2020 10:14 am
Forum: Graphics, sound and multimedia
Topic: wm8731 can not work.........
Replies: 0
Views: 138

wm8731 can not work.........

I have layout a pcb about wm8731/pwmaudio/Arduino/RTC for raspberrypi 4b and cm3. everything is ok but WM8731.... base on I2C i already set rtc is ok. i can switch audio cards in Aduio Outpus and Audio Inputs seclection with audioinjector-pi-soundcard. and i2s can get pluse by oscilloscope.but nothi...
by fuwen0202
Thu Jun 04, 2020 9:22 am
Forum: Device Tree
Topic: raspberry pi 4B PWM audio do not work
Replies: 7
Views: 849

Re: raspberry pi 4B PWM audio do not work

i have try GPIO12and13,with “dtoverlay=audremap,pins_12_13“ and let ”dtparam=audio=on“ without “#”
it can works will,but enable_jack=on, can not let 3.5AUX output in the sametime.

and "dtoverlay=pwm-2chan,pin=12,func=4,pin2=13,func2=4" can not work. i think it need mapping.
by fuwen0202
Wed Apr 22, 2020 8:46 am
Forum: Compute Module
Topic: Some Questions about IO and Reuse Functionality
Replies: 5
Views: 751

Re: Some Questions about IO and Reuse Functionality

thanks for u answer my confused so accurate,6by9。 about Q1:after read <dt-blob.dts>, https://www.raspberrypi.org/documentation/hardware/computemodule/cm-peri-sw-guide.md https://www.raspberrypi.org/documentation/configuration/pin-configuration.md https://www.raspberrypi.org/documentation/configurati...
by fuwen0202
Sat Apr 18, 2020 3:57 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread. [I2S works]
Replies: 993
Views: 540781

Re: STICKY: The I2S sound thread. [I2S works]

In continuation to ^^, I've been able to build a basic driver with DKMS and it can be found in /lib/modules/.../kernel/sound/soc/bcm/snd-soc-<mydriver>.ko. I've added this to /etc/modules and when running dmesg I get: `[ 2.204423] snd_soc_<mydriver>: loading out-of-tree module taints kernel.` but t...
by fuwen0202
Tue Apr 14, 2020 4:02 am
Forum: Compute Module
Topic: Some Questions about IO and Reuse Functionality
Replies: 5
Views: 751

Re: Some Questions about IO and Reuse Functionality

The SD1 controller is perfectly capable of working in 4-bit mode - that's how we use it to drive the WiFi interface - but it means that you need good connectivity with short wires of equal length to all 4 DAT lines. Without that you will see signal integrity problems and hardware errors. after layo...
by fuwen0202
Tue Mar 31, 2020 4:45 am
Forum: Compute Module
Topic: Some Questions about IO and Reuse Functionality
Replies: 5
Views: 751

Re: Some Questions about IO and Reuse Functionality

hi , i has the a little question of SD1, Raspberry Pi CM3+ with 2020-02-13-raspbian-buster.img add line in /boot/config.txt --------------------------------------------------------TEST 1 -------------------------------------------------------------- <dtoverlay=sdio,poll_once=0> plug in SD befroe pow...
by fuwen0202
Fri Mar 13, 2020 8:37 am
Forum: Compute Module
Topic: Some Questions about IO and Reuse Functionality
Replies: 5
Views: 751

Some Questions about IO and Reuse Functionality

For the compute module CM3 and CM3+ , I have made the first version of PCB base on CMIO add HUB, and it can enter the system normally and use some USB devices (SATA【asm1153】,Wifi,HUB【f2.1】)。 Now,in Second version,i want add some additional features base on GPIO。After view the datasheet and device tr...
by fuwen0202
Mon Mar 09, 2020 3:31 pm
Forum: Compute Module
Topic: some questions about schematics for the Compute Module IO board (CMIO)
Replies: 5
Views: 754

Re: some questions about schematics for the Compute Module IO board (CMIO)

i just layout LAN9500A usb2lan IC, without test。。。。if u need,say a words
by fuwen0202
Mon Mar 09, 2020 3:25 pm
Forum: Compute Module
Topic: Compute Module Power Supply Design/Budget
Replies: 6
Views: 1485

Re: Compute Module Power Supply Design/Budget

6by9 wrote:
Thu Dec 05, 2019 9:30 pm
The reference regulator design is on the CMIO schematics - https://www.raspberrypi.org/documentati ... IO_3p0.zip
PAM2306 is a DUAL STEP-DOWN DC-DC CONVERTER 1A output each Channel for 3.3V & 1.8V。
by fuwen0202
Mon Mar 09, 2020 3:20 pm
Forum: Compute Module
Topic: Capacitors on schematics
Replies: 1
Views: 557

Re: Capacitors on schematics

you mean PAM2306? datasheet demo used 4.7uF in Vin and 10uF in Vout
by fuwen0202
Mon Mar 09, 2020 2:44 pm
Forum: Compute Module
Topic: Compute Module RUN pin
Replies: 7
Views: 1181

Re: Compute Module RUN pin

I have no idea on your design, but if there would be the need for me to 'disconnect power' I would do this on the PMIC by using it's enable signal. This will then really switch of power Anyhow, holding the device in reset for a longer periid shouldn't be a problem. Hi I designed in a way that, when...
by fuwen0202
Mon Mar 09, 2020 2:21 pm
Forum: Compute Module
Topic: SD on CM3 module
Replies: 27
Views: 13834

Re: SD on CM3 module

if u want boot from second sd card ,why dont you add a SD to USB ic,then just use SD card as a usb disk。use EMCC_DISABLE_N to GND ,boot from USB。

if u just want use second sd card ,u can use GPIO 22-27 or 34-43
by fuwen0202
Mon Mar 09, 2020 2:07 pm
Forum: Compute Module
Topic: CM3+ - Connecting LAN9512, but also get USB Slave functionality?
Replies: 8
Views: 979

Re: CM3+ - Connecting LAN9512, but also get USB Slave functionality?

I used a hub ic named fe2.1,then use lan9500 for lan

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