This repository contains the firmware, PCB artwork and case designs for an 1/6th scale Macintosh Plus model. The entire project, including the schematics (well, for what they're worth) is documented on http://spritesmods.com/?art=minimacplus .

The firmware for this build runs on an ESP32-Wrover module. To compile this, you need an Xtensa-toolchain and ESP-IDF, the SDK for the ESP32 in the ESP32-Wrover module. You can find instructions on how to install these on the Espressif ESP-IDF github page: https://github.com/espressif/esp-idf

This firmware can also be compiled for an ESP32-Wrover-Kit development board, provided it contains the Wrover module with the 4MiB additional PSRAM. To do this, run make menuconfig and under component config, Tiny Mac Emulator options, select the Wrover-Kit display. Depending on your devboard, you may also need to lower the SPI flash/psram clock speed: set make menuconfig -> serial flasher config -> Flash SPI speed to 40MHz if you get crashes or if the memory test fails.

The emulator needs a Macintosh Plus ROM file in order to function. This ROM file is still copyrighted by Apple, and as such is not distributed with the source code. If you obtain it, you can use the firmware/flashrom.sh file to flash it, or manually flash it to address 0x100000.

The emulator needs a hard disk image to boot from. For an un-modified partitions.csv on a 4MiB flash device, this image needs to be 1433600 bytes, or 2800 512-byte-sized blocks. The hard disk image needs a version of the Macintosh operating system installed. The easiest way to do this, in my experience, is using the Mac Plus emulator in MESS:

• Create a HD image of the correct size: chdman createhd -o my_hd.chd -s 1433600
• Install stuff on this HD image, Refer to e.g. https://mamedev.emulab.it/etabeta/2010/04/10/mess-how-to-episode-ii-apple-macintosh-plus/ on how to do this.
• Extract the raw HD image: chdman createraw -i my_hd.chd -o my_hd.img
• Flash my_hd.img to the ESP32 using flashhd.sh or by manually flashing it to address 0x120000.

A good trick on Linux to move files from your host OS to these images is mounting them. As root:

• Enable partition support for loop-mounted block devices: rmmod loop; modprobe loop max_part=8
• Setup the image as a blockdevice: losetup /dev/loop0 my_hd.img
• Mount the partition: mount /dev/loop0p1 /mnt
• Move stuff from/to /mnt
• Umount the partition: umount /mnt
• Remove the loop: losetup -d /dev/loop0
• Flash the image

Note that 'hard disks' created in e.g. MiniVMac or BasiliskII will not work, as they actually are hacked floppy images and as such are missing the partition table and hard disk driver.