Spyke

6502/65816/Z80 on the same bus

I like the hacked breadboards so far. I made a sloppy super-breadboard. I should have glued it before soldering but was worried the glue might make it into the slots with the metal contacts. I also broke up the internal rails and labeled so that 8b data and 16b address all exist on the same set of 4 power rails.

I think I am having an issue with either some crossed wires or how Bus Request works with the Z80 versus how the Bus Enable of the 65x chips work. I think one or all may have some type of routine that does not high-z the buses immediately... a problem for tomorrow.

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retrocomputers·Retro ComputersbyBlisscast

Turn your dumb terminal into a workstation today, with X Window System! – GUI Wonderland

What if you used a late 80s Unix system for your job or university, but still wanted a nice and pretty GUI to use? Well then, let’s discover a nice selection of window managers and graphical user interfaces that will make your boring installation look awesome!

Turn your dumb terminal into a workstation today, with X Window System! – GUI Wonderlandhttps://blisscast.wordpress.com/2025/11/11/x-window-system-twm-unix-gui-wonderland-11Open linkView original on lemmy.world

Why doesn't everyone use battery backed SRAM for retro projects and breadboarding?

Looking through my regular SRAM chips, most have a standby mode with just a few micro amps of current draw and function down to 2 volts. So, a perfect match for one of these and a coin cell. That makes programming from scratch easy, and one can iterate without a ROM programmer. Once a subroutine is verified, it can be transferred to an EEPROM. Then there is no fussing with paged erasure, not that erasure is a big deal. It just requires the subroutine and a 12 volt source.

Anyways, the battery backed SRAM on the board is the plan for tomorrow. I might have expanded the real estate a bit today, and built a custom breadboard for the 68k Hershey bar. I don't know if I will mess with the 68k stuff as all chips I have are NMOS, and I think that means they cannot single step through code. Reading up on the Z80, that thing is really really nice compared to the 6502.

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DIP 💩 puzzle game

::: spoiler One of many little eccentric labels made to stop rerere-referencing datasheets for pinouts and functions. Pulling EN-Latch low takes in the address on pins A0-A3 and latches it. Each of these have an X in the lookup table box for the bit position they control. The Y pins have a corresponding table where the black boxes are Boolean 1/address pin high values. The output enable pin sets the previously latched addressed Y pin high. This chip is typically used as glue logic for selecting peripheral circuits, like when extending memory beyond the address space available to a processor. So if 64k is the whole address range, and the 74HC4514 is connected with every Y pin connected to the chip enable(s) of an additional 64k of mapped memory, it is possible to address over 1 megabyte. :::

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retrocomputers·Retro Computersbyrcmd

This little pebble-shaped fella was the first machine I got a taste of Linux on

Meet Motorola ROKR E2, an almost unknown successor of the infamous iTunes phone ROKR E1. The device was one of the first candybar style non-touchscreen phones on the market running Linux. When connected to a PC it can present itself as a network device. Running telnet against the IP address of a network interface exposed BASH, where I had a chance to learn UNIX scripting.

More about Motorola ROKR E2 here.

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