After adding some bypass capacitors and fixing some forgotten nets, I confirm basic ROM, RAM, and I/O work on the new board. Next, I'll add the RS-232 hardware and test.
Sockets are starting to arrive.
I'm up to 7 breadboards and 11 ICs. The scope shows how sloppy the clock signal gets as it goes over long wires from the oscillator to the I/O and sound chips. I've seen no functional problems at 1 MHz system clock, in spite of this.
Now that I have desktop -> 6502 serial program transfer working, I can test code much more quickly. Time to start working on LCD display routines.
Looks like the display memory is mapped funny, so the auto-increment feature goes from line 1, to 3, to 2, to 4. I'll need to manage the display memory manually.
Implemented basic 2-way communication between my desktop and a microcontroller using the w65c51/max232. Now that I understand these chips, the next thing is to add support for them to the emulator for my 6502 machine. Then I'll write and test the serial port routines before moving it all over to hardware again.
Working with the MAX232E today. One of the next things I want to implement on my 6502-based computer is a serial port. This would let me update its program from my desktop computer.
The desktop's serial port will use ~12V logic signals. Since I'm working with TTL/CMOS, I'll use the MAX232E to convert between 12V/5V.
I took a bit of pride in my home network this morning. Got all that cable slack off the floor and each one bundled before it reaches the (newly installed) patch panel. I'd like to neaten up the device CAT5 routing too, but I only have a handful of devices, so it's not critical. It would be fun to build a rack one day, but I'm not sure if I'll ever use devices to need one.
Early work on parsing nested expressions. This concludes my parser work for the weekend.
Coming pretty close to parsing a "Hello, world" C program.