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I think we are feature- and bug-complete for the first part of the UI, which is the pattern editor. I'll get this ready for release and push master.

This makes vtracker a bit more usable, but it still needs an instrument editor and track editor before it has a complete user interface.

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Just registered for and plan to attend Cactuscon 2019:

I finished this small assembly language LCD demo in time for our meeting this past Tuesday. The next thing to do is add RAM so programs can use a stack. After that, I want to make the computer load its start program from my desktop over serial port; reprogramming EEPROM every time is too cumbersome.

65C02, 65C22, and LCD are presumably wired correctly and a test program is assembled. My EEPROM programmer isn't correctly writing some memory locations, though. I noticed I'm not quite meeting the timing requirements for the write procedure, so I'm working on a new EEPROM programmer circuit now.

Working on address decoding and getting some wire paths cleaned up today. Optimistically, I'd like to be able to show off controlling the LCD display with assembly language programs at my -com-eng meetup on Tuesday.

Fritz boosted

I just had one of my favourite classic-sounding quotes brought to mind: "What is man? A miserable little pile of secrets" from Castlvania: Symphony of the Night.


Or at least not originally. It wasn't in the original Japanese at all, it was added by the English translator, AND they copied it word for word from a 1967 book by the French writer André Malraux.

While cool, I'm still a tiny bit disappointed.

Via the EXCELLENT Legend's of Localization:

Good morning . Looking forward to striking up conversations with people sitting next to me.

Working on the Arduino-based keyboard controller I'll use for my 65C02 computer. I'll start very simple. The controller will have a small internal buffer of keys that have been typed. It will deliver the scan code for each typed key to the processor, one by one, as the processor requests them.

@vertigo I also noticed the Wikipedia entry has a very nice overview of the internals And the Forth-79 standard seems pretty digestible, at 50 pages

Regarding implementing a Forth, that is still some months away, but I've started to look into it. I've been reading the source code for JonesForth, and intend to take notes on the fig-forth source code as well. @vertigo, any other recommended material on understanding Forth's internals?

The last thing I want to emulate before moving back to the breadboard is a keyboard controller. Once I have a program to echo user keystrokes on the display in the emulator, it'll be time to move back to the hardware and bring it to parity with the emulator.

I have enough of the 65C22 emulated to drive the character LCD from an assembly language program:

Time to wrap up a few small things and quit for the day.

I don't know of such a standard, but I'd be interested if one exists. I'm gluing them together in C code.

I'm emulating a hardware computer I'm building around the 65C02 processor. The goal in this case is to be able to test ideas as thoroughly as possible in the software emulator before moving them to the hardware.

Character LCD emulation is working. Now I'll work on emulating the 6522.

I want to experiment with some interrupt and I/O routines before trying them on the hardware, so I'm looking for a 6502 core to use in an emulator. Here are a couple candidates I'll look into:

6502 primer shows a circuit to extend the number of input bits for the 65C22 shift register, which is just what I need to handle 11-bit PS/2 keyboard scan codes. After I integrate this and the LCD with the 65C02, all the hardware is in place for a complete user I/O loop.

Then I'll start work on my first piece of software for this new machine: a forth environment. I've begun reading through JonesForth to prepare.

Fritz boosted

Having covered the theory behind OpenGL the last two days ( ), I know want to start studying how Mesa3D implements it.

To keep things clear (for both myself and all of you) I will only describe the drivers for X86 & Radeon Graphics, which I chose because that's what my laptop has.

I will cover it in top-down order of the following days. And while it should quickly become irrelevant, I'm being guided by some trivial sample code of their's.

I have 2 keyboards that fall back to PS/2 compatibility when connected through a USB-to-PS/2 adapter, which I happened to have. I confirmed they are sending their make/break signals.

Next is to communicate with the keyboard using the 65C22. It seems using the VIA's shift register is the best way to do that.

Got familiar with the 65C22 VIA. Testing the LCD display through it went fine.

Now to try to talk to a keyboard. Not sure whether or not any of the ones I have are PS/2 compatible.

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