True to hardware, our SWIM and SuperDrive emulation supports 400K, 800K, and 1.44MB floppies interchangeably, and you can read/write 800K disks on the 1.44MB drive. Emulating these enabled support for reading copy-protected images (also on the Apple IIgs) as well as 1.44MB high-density floppies. The next big step was brand new emulation by Olivier Galibert of the 4 major Apple floppy disk controllers, the IWM (Integrated Woz Machine, so-named because it was Steve Wozniak’s original disk controller on a single chip), SWIM (Sander/Wozniak Integrated Machine), SWIM2, and SWIM3. This exposed an issue with our 68HC05EG emulation where it was using the wrong cycle counts fixing that brought the emulated ADB bit cells into spec. There is also partial ADB (Apple Desktop Bus a USB-like way of connecting the keyboard/mouse) support working now on the Portable and PowerBook 100.Īs part of that work, we needed to slow the ADB simulation down to match the speed of real hardware, and Olivier Galibert came up with a more accurate way to emulate the wait states incurred by the Mac’s main CPU when it was accessing certain chips in the system. The PMUs on these machines were Mitsubishi M50753 microcontrollers, and the emulation for that chip was improved by AJR and myself to make this possible.

The PMUs are microcontrollers that handle power management and control and also Apple Desktop Bus interfacing.

The Portable and PowerBook 1xx series got improved video emulation and we now emulate their Power Management Units (PMUs) by running their original Apple code. (PDM is “PiltDown Man”, the codename of the 6100 early PowerMacs were named for famous scientific hoaxes).Īll of these drivers got cleanup and modernization along the way.

The “classic” black and white 68000 Macs went to mac128.cpp, the Portable and PowerBook 100 went to macprtb.cpp, the 68030 PowerBooks went to macpwrbk030.cpp, the Quadra 700 went to macquadra700.cpp, and the PowerMac 6100 went to macpdm.cpp. Things started off with my splitting the large, ugly, unwieldy mac.cpp driver into several new drivers. We’ve had lots of movement so far in 2021 on the 80s/90s Macintosh drivers, so let’s talk about it a bit.

Mess mac plus emulator