It has most of the functionality of the Discovery one, but has a few improvements:
USB ports are on the breakout, so there’s proper USB B
USB A “host” - still need to test this, but it’s normally done setting the ID pin low. I’ve put a panel switch for selecting host/slave and there’s a jumper to power the slaved device if needed.
LEDs and reset button on the panel; “blue button” as a jumper
a 3.5mm socket for a footswitch or gate (or for other purposes)
some connectors for +5V supply direct off the USB bus
3v3 Vreg is rated at 1000mA I think
the panel connectors could be distant from the Core
I haven’t tested the AINs, but it is possible to use an external reference.
At the moment I have the breakout mounted on female headers; I suppose they could be directly soldered if extra height is needed. The JTAG and other pin headers do take up a bit of vertical height. These could be cut off if needed; the breakout pins are still there on the headers. There is a realtime clock oscillator (and caps) that I removed as they overlapped with a port.
A downside compared to Discovery is that there isn’t any ST-Link. This is easily overcome with a cheap ST-link clone, or even an old Discovery board could be used.
At least all of the functions for a SEQ are working well. I realise that some of the cabling etc. is a bit wonky for the moment.
So even a bit higher than the Disco version with the bottom headers; about the same without. There’s not much reason to keep the panel board close to the Core, although I will do it like that for the SEQ and everything aligns nicely. I suppose the signal integrity (USB, SD) is better with shorter cables.
The panel connectors are themselves quite high. Honestly, I think the only way to do it shorter height-wise would be with a dedicated STM32F4 chip on a custom PCB. With a breakout it’s fairly much plug-and-play, and probably cheaper.
Honestly, I think the only way to do it shorter height-wise would be with a dedicated STM32F4 chip on a custom PCB. With a breakout it’s fairly much plug-and-play, and probably cheaper.
I did one but never manufacture the board then never test it. It’s a good way to gain space, the board is really small, but if you’re not afraid about small smd components.
I have to remember exactly which package I use, but same CPU, there’s exactly the same port as usual, except J11 which is a 6 midi ports and USB, two tact, micro-SD on board.
I can share if you want it…
Bruno, looks nice! Your offer is kind, but I think it will be okay with what I have. In my experience, builders have quite some trouble even with SOIC parts, so I try to go no smaller than SOIC/1206/SOT-23. And of course THT parts when possible as they make nice jumpers!
I think the Waveshare paradigm is a good one to follow as they do a lot of STM chips:
Yannick, I need some weeks at least to talk with the Bavarians. I also have to prioritise giving boards out to those interested in the SEQ. But hopefully more becomes clear soon.
In my experience, builders have quite some trouble even with SOIC parts
Yes i know that’s one of the reason i didn’t share it, some soldering experience and a lot of flux paste is necessary, obviously some good equipment and tool too.
