Mt32-pi Internal Hat (Retrofit Kit)

Description

This kit is ONLY for owners of the Ironclad Plus prior to Batch 4, which doesn´t have the dedicated on-board header labeled “Pi-CONN” (to the left of the fan headers and i2c/spi holes, over where the RTC bridge plugs in), and uses the 5 volts fan connector as power source for the Pi.

This kit has been discontinued and is here only for future reference to keep the installation instructions available.

This kit allows to internally install a Raspberry-Pi Zero 2w to work as an mt32-Pi. It connects on top of your DE10-Nano to the second user i/o port, which frees the use of the primary port for SNAC devices or other peripherals at the same time, and is powered by the Ironclad Plus with the supplied cable. Everything remains internal and nice, no more connecting and disconnecting stuff to switch between SNAC controllers, guns, etc, and the mt32-pi. The definitive solution to have everything on your MiSTer build!

It has headers to optionally wire your own “Rom” and “Synth” buttons, or connecting an external Oled display for the looks, this is completely non necessary though, as this functions can be controlled inside the MiSTer cores menu, and the “oled” can be shown on the TV screen. But the possibility is there for you modders out there.

The Hat also has two holes to screw a 40mm fan on top of the FPGA, this is usually non necessary, specially if you bought the “Massive Heatsink” along with your Ironclad, as a single fan extracting hot air from the case is enough, but I have seen some Mini-ITX cases that don’t have a single place to properly screw a FAN, and in that situation this addition becomes really handy. A suggested fan model for this purpose might be the Noctua NF-A4x10 PWM for example, but any 40mm fan will fit and work, be it PWM or not, as usual. Note that only PWM fans (4-pins) benefit from the automatic thermal fan control or adjustable speed from the Ironclad Plus.

The kit includes:

• The mt32-Pi hat.
• All screws and Stand-offs needed for installation.
• 2-pin female to female cable for power. CAUTION, READ INSTRUCTIONS.
• Smaller and redesigned RTC bridge for the Ironclad Plus.

This Hat is only intended for the Raspberry-Pi Zero 2w and, maybe, future “Zero” models the Mt32-Pi project might support. A standard sized Raspberry-Pi will not fit. A ribbon IDC extension cable might help with that, but you are on your own in that adventure 😉

INSTRUCTIONS:

This installation instructions assume you already have a working Raspberry-Pi Zero 2w with the GPIO header already soldered. Also, installing and configuring the MT32-pi software to work in your Pi is out of the scope of this instructions, you can follow THIS easy guide from the mt32-pi official wiki.

1. Screw the three short stand-offs to the three small holes of the Hat, and Connect your Raspberry-Pi Zero 2w to the Hat from below, making sure it is not backwards and the three standoffs are correctly aligned with the Pi’s holes. If that is correct, screw the Pi to the hat.
2. If you are attaching a fan to the Hat, now is the time to do it.
3. Remove your old fat RTC Bridge and replace it with the new sportive provided one.
4. With your Ironclad setup properly built replace the two screws at the corners closer to the DE10’s LAN port with the long standoffs supplied.
5. Place your Pi-sandwich on top of the DE10 as shown in the images, making sure the bottom 8-pin male header aligns correctly with the rightmost female header pins on the DE10, once you are sure, press it down, the holes of the Hat should align properly with the long standoffs you installed before, if so, use your previously removed screws from the DE10 to screw the Hat in its place over the standoffs.
6. The mt32-pi hat has two pins labeled “5v IN” or “5v IN ALT“on top, one with a “+” and other with a “–” mark, those pins are for supplying power to the Pi. To do that you can use the “5v Fan” 3-pin header on your Ironclad Plus, DON’T use any of the other fan headers labeled with PWM as they carry 12 volts. The pin in the middle is the “+“, and the bottom pin is the “–“, use the supplied 2-pin cable to interconnect the hat with that fan header and be EXTRA cautious to keep polarity, if you don’t do it, bad things will happen, your DE10 is fairly well protected by the Ironclad against something like that though, but better don’t try your luck and double or triple check. If you prefer, and are an experienced user, you can alternatively supply power to the Hat from the ATX power supply hard disk connectors, or any other reliable, and powerful enough, 5 volts source you like, but don’t think about feeding power to the Pi from the DE10-nano 5 volts GPIO pins, this can kill it. See the diagram picture between this product’s images.

The mt32-pi internal hat uses the secondary user i/o port so, for now, it needs modified cores to work, you can replace your existing cores or have both installed at the same time. Work is been done to include this cores into update_all script to make things easier, it will be available soon  For now you can download the modified cores from here (download the “+” versions):

MiSTer Mt32-Pi UserIO2 Cores (Updated 2023/02/16)