#dvioutput

[adafruit]

Fruit Jam RP2350B credit-card mini computer with all the fixin's 🍓🍇💾

We were catching up on a recent Hackaday hackchat with Eben Upton (https://hackaday.io/event/202122-raspberry-pi-hack-chat-with-eben-upton) and learned some fun facts: such as the DVI hack for the RP2040 was inspired by a device called the IchigoJam (https://www.hackster.io/news/ichigojam-combines-strawberry-and-raspberry-to-deliver-a-raspberry-pi-pico-powered-educational-micro-66aa5d2f6eec). We remember reading about this back when it was an LPC1114, now it uses an RP2040. Well, we're wrapping up the Metro RP2350 (https://www.adafruit.com/product/6003), and lately, we've been joking around that with DVI output and USB Host support via bit-banged PIO, you could sorta build a little stand-alone computer. Well, one pear-green-tea-fueled-afternoon later we tried our hand at designing a 'credit card sized' computer - that's 3.375" x 2.125", about the same size as a business card (https://hackaday.com/2024/05/07/the-2024-business-card-challenge-starts-now/) and turns out there's even a standard named for it: ISO/IEC 7810 ID-1 (https://www.iso.org/standard/70483.html).

Anyhow, with the extra pins of the QFN-80 RP2350B, we're able to jam a ridonkulous amount of hardware into this shape: RP2350B dual 150MHz Cortex M33 w/ PicoProbe debug port, 16 MB Flash + 8 MB PSRAM, USB type C for bootloading/USB client, Micro SD card with SPI or SDIO, DVI output on the HSTX port, I2S stereo headphone + mono speaker via the TLV320DAC3100 (https://www.digikey.com/en/products/detail/texas-instruments/tlv320dac3100irhbt/2353656), 2-port USB type A hub for both keyboard and mouse or game controllers, chunky on-off switch, Stemma QT I2C + Stemma classic JST 3-pin, EYESPI for TFT displays, 5x NeoPixels, 3x tactile switches, and a 16-pin socket header with 10 A/D GPIO + 5V/3V/GND power pins. The PSRAM will help when we want to do things like run emulations that we need to store in fast RAM access, and it will also let us use the main SRAM as the DVI video buffer.

When we get the PCBs back and assembled, what should we try running on this hardware? We're pretty sure it can run DOOM. Should that be first? :) We also need a name. Right now, we're just calling it Fruit Jam since it's inspired by the IchigoJam project.

[adafruit]

We designed and prototyped an RP2350 Metro a few months ago, and it worked OK, but we were really short on pins, which meant a lot of annoying compromises - so we ended up only fabbing the RP2350 Feather to start. With that design flying off the shelves, It's time to revisit the Metro. We wanted to jam-pack this design, and with the extra GPIO on the B we have plenty of peripherals: the 22-pin HSTX for DVI output, Stemma QT port, NeoPixel, JST 3-SH SWD debug port, 16MB flash, an extra spot for PSRAM, MicroSD card with SPI or SDIO connections, and 5V buck converter that can give us 2 Amp easily, which we'll need since we also have a USB Host port pinout for connecting USB peripherals. We even managed to get a couple of niceties like switchable power for the USB host power, a USB boot button as user input, and an SD card detect GPIO.

[adafruit]

HSTX DVI output on Fruit Jam! 🎨🖥️🎶🚀🔌

Woo! This xscreensaver-like demo shows random lines and colors displaying on a mini 7-inch HDMI monitor

it's a 320x240 'pixel doubled' display that is running from the Fruit Jam, an RP2350-based mini computer board

But what's cool is that we're now using the HSTX interface rather than PIO+core bit-banging. That means we now have plenty of extra resources for running the USB host… which is still being worked on.

[adafruit]

HSTX to DVI adapter board for RP2350

For our new RP2350 boards (https://www.adafruit.com/search?q=rp2350), we are interested in the new HSTX (high-speed transmission) peripheral, which allows the chip to do DVI output with four differential lanes - 3 data and one clock - and no PIO usage. We added a 22-pin 0.5mm pitch FPC connector to the Feather and Metro and routed it like the Raspberry Pi DSI connector. You'd first want to connect it to an HDMI display, so here's an HSTX->DVI adapter board. There are a few extra parts since we need to generate 5V and then level shift the I2C / DDC pins.

[adafruit]

Desk of Ladyada - More TLV320 DAC'ing with a Bit of a Run-around 🎧🔍 https://youtu.be/gge8sFjypnQ

This week - We tackle the TLV320DAC3100, fixing headphone & mic issues for a breakout board. Plan to use it in AudioFX remake. Jepler advanced HSTX DVI text mode for Fruit Jam. Also, a search for a new pocket multimeter begins as the fave Amprobe PM51A is discontinued.