I am definitely stealing Dmcke5's thunder with this post, but wow, this is absolutely going to be one hell of a sexy beast!
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Worklog Retro Lite CM4 - A StonedEdge and Dmcke5 collaboration
- Thread starter Dmcke5
- Start date
I've seen those mipi displays around eBay, if I were doing my own pi 4b unit would you recommend getting my hands on one of those displays? Most I've seen were about 2k resolution but I have also looked at the HDMI to 40pin TTL 5" setups on adafruit they just weren't ips
We didn't end up using one as we wanted to be able to integrate the display controller into our own PCB as we didn't have room for another separate LCD controller PCB and couldn't find any reliable open source designs for controlling MIPI displays. So we went with a 40 pin TTL display with the adafruit HDMI controller instead. There are plenty of 40 pin TTL displays around which are IPS, it may just take some trial and error to find one that's 100% compatible with the adafruit driver board.
Dmcke5 took the time out yesterday to create some more renders for the project to give us both an idea of the color combinations we could possibly achieve with the anodized finishes. I'll post them below in spoilers so it doesn't clog up the worklog.
I just received the CM4 Lite module in the post today and hopefully may have a bit of time this weekend to get started on the main PCB assembly and do some preliminary testing. I'm confident that with the incredible progress Dmcke5 has made over the past weekend with the housing, we will get this done soon! Dmcke5 is confident that with our button molds and some clever mixing of resins we will be able to achieve whatever button colors we want, which opens the floodgates for testing out some awesome color combinations in Fusion 360's rendering environment.
Enjoy the renders! (The below picture is raw 6061 aluminum finish, no post processing has been applied except for a sand blast)
I just received the CM4 Lite module in the post today and hopefully may have a bit of time this weekend to get started on the main PCB assembly and do some preliminary testing. I'm confident that with the incredible progress Dmcke5 has made over the past weekend with the housing, we will get this done soon! Dmcke5 is confident that with our button molds and some clever mixing of resins we will be able to achieve whatever button colors we want, which opens the floodgates for testing out some awesome color combinations in Fusion 360's rendering environment.
Enjoy the renders! (The below picture is raw 6061 aluminum finish, no post processing has been applied except for a sand blast)
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I'll take one in yellow switch light theme !!! Looks awesome guys.
I took 2.5 hours today to assemble most of the parts that were in stock at Digikey. I need to get some flux to fix all the shorts but very happy on how it looks. Hopefully within the next 2 weekends or so I can dedicate some time to testing out all the circuits and writing the code along with Dmcke5 for the BQ24292i and MAX17055 fuel gauge.
Exciting!
Exciting!
Official finished case before we go in for anodizing hopefully this week. I’m still in awe of the job Dmcke5 has done on it, it definitely deserves to have better electronics in there than what I am capable of... maybe next revision
I also got 15V out of the Nintendo Switch Lite charger which was pretty easy to do with the IP2721 sink IC. Thanks to YveltalGriffin for suggesting this easy to use solution. It’s not as fancy as it can’t negotiate over i2c but it’s good enough for a basic Pi project.
I also got 15V out of the Nintendo Switch Lite charger which was pretty easy to do with the IP2721 sink IC. Thanks to YveltalGriffin for suggesting this easy to use solution. It’s not as fancy as it can’t negotiate over i2c but it’s good enough for a basic Pi project.
I'm not completely sure on the exact specs of the RVL PMS but assuming it can provide about 3 amps at 5v then yes it will be adequate for a pi4. There's no need for a 3.3v supply as the pi has its own built in 3.3v regulator for anything it needs. 10000mah would get you probably 5-6 hours of run time easily.
Thanks, I can't say about the rails from the 5v buck but the BOM lists a 5v 4a buck boost for the PMS, the 3.3 was to have the uamp analog added in. I believe the pi 3.3 rail was not adequate enough for larger power draw
I think the pi's 3.3v regulator can handle a couple of hundred milliamps. Have you considered one of the many digital audio options available for the pi? That's the direction I would go personally.
There aren't any DAC outputs on the Pi SoC or CM, so you won't be able to use the U-AMP with the Raspberry Pi. The Pi model A/B do it by using the PWM peripheral and a low pass filter. If you want to use the U-AMP you'd have to modify the code to set it up as a i2s master device and set the Pi as an i2s slave, with external MCLK for managing the timing of all the signals. Another possibility is to use the pins for DPI, but then use SPI or even possibly bit-banging, to attach a cheap external MCU with I2S which deals with a DAC or CODEC. The Pi doesn't have a decent MCLK at all, so nearly everyone I've spoken to goes with the PCM5102 chip for audio. We went with the WM8960 codec from Waveshare, since there is already a bunch of Linux drivers for it.
Yep, the internal 1v8 and 3v3 regulator outputs for the CM4 can supply up to 600mA
I really wasn't plannning on using i2s from the pi to the uamp, I was going to pull headphone audio out to the analoge on the uamp, it's been done plenty of times for the pam8403. Just keeping it simple.
That’s fine, but maybe I wasn’t clear in the above post. There is no DAC outputs on the Raspberry Pi, so you can’t use it to drive an analog amplifier.
Actually there is on the full sized Pi4, its just the Compute module that doesn't have one.
Oh, my mistake then - I think the Pi Zero also doesn’t have any analog outputs. I guess then a generic analog amp will work fine then for other models. You’d still need a way to drive both headphones and speakers too though. U-AMP seems like a good solution for what he wants to do then.