![]() ![]() Figure 4(a) depicts a small patch of this digital video output interpreted as black and white pixels. The Apple II+ uses a trick to generate the modulated signal: it produces a digital signal that switches at 14.31818 MHz-exactly four times the colorburst frequency. A color television demodulates and combines linear ratios of these signals to recover red, green, and blue intensities. ![]() To a high-bandwidth luminance (brightness only) signal (about 3 MHz) called Y, NTSC adds two lower-bandwidth color signals (“I” and “Q”) that are quadrature modulated at 3.579545 MHz. ![]() Unlike VGA, whichĬonveys separate red, green, and blue signals, composite (color) NTSC video consists of three signals modulated together. Interpreting colors is the bigger challenge in converting the Apple II+ output to color VGA signals. Function keys seem like a good option:į4 - 80/40 (this is a toggle switch on my Apple IIc, not sure about IIe)į5 - Keyboard (this is a toggle switch on my Apple IIc, not sure about IIe) Perhaps have a second option for the right alt / closed apple key in case people have US keyboards. Left and Right Alt seems perfect, except on US keyboards. Every key should be available on the keyboard (not the user button). In my opinion, each key should act as it should (backspace should be the printed cursor). I definitely appreciate the help in getting this better. I assume this means I can change my keyboard type on my MiSTer and get right-alt to work. (US International keyboard?) Any recommendations? Edit: I was able to set up my keyboard as US International in Windows 10, and now when I press right Alt, it highlights Ctrl-Alt on the keyboardtester website. I would be willing to get a different keyboard for the MiSTer if I have to as long as most of the other keys are still the same. On US keyboards, is there a way to detect left and right alt? Is right alt called "Alt Gr"? If I go to both Alt's highlight when I press either. It's probably not a big deal to add the necessary stuff to the keyboard controller, but it's a bit more than just adding new key codes. Under the hood, they're just wired to the paddle/joystick button inputs, so there are no new key codes or register bits involved with them (and yes, it's possible to use the joystick buttons to do a full reboot or run the self-test). The open/closed apple keys are interesting, and I wonder if they were omitted when overhauling the core because in a sense, they weren't new to the IIe. The user button mapping is kind of a conundrum because there's a clash between MiSTer conventions and Apple IIe conventions. ![]() I think on the original Apple II and II+ the reset key alone asserted the reset signal (which it does on the current core), while later models required the combination of Ctrl+Reset to prevent accidental resets (and Ctrl+open apple+Reset to do a full reboot or Ctrl+closed apple+Reset to run the self-test). Reset is currently mapped to the user button and LAlt+LCtrl+RAlt (by default there are a few options in MiSTer.ini). If someone wants to make another mapping, it shouldn't really require much vhdl / verilog knowledge. If you want it as a replacement for the original, then the original layout makes a bit more sense. I find it really hard to use the cores in the original layout when you just want to play a few games. I like the idea of having an option to switch it to a PC layout. That said, left, right alt for open and closed apple, makes sense. If there's an option to select the 'PC Keyboard' I pick it first thing. The PC emulators I use mostly use PC layouts, and it's a quirk of mister, hunting around in oddball cores to find where the '*' key is. Maybe for the UK cores, the keyboard layout is 'part of the thing,' but with Apple 2, there were all kinds of keyboard layouts, and they eventually evolved towards the PC style layout in the end. ![]()
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