Commander X16

On 10/11/2022 at 12:17 AM, Cyber said:

Cool setup!



I also like to make such projects work without modern computer. In my case I use ASCII Video Terminal (https://geoffg.net/terminal.html). I think it is pretty much similar thing to uTerm, just a different implementation and taste.

Yeah, it's a lot of fun to build and use! Now I'm working on getting it into a proper case.

I looked at that terminal, very similar to the uTerm-S (Standalone), and really liked it, simple and effective. I like the addition of composite video and menu options! Two things not on the uTerm, at least not that I'm aware of. Though there is modded firmware that does add a menu and some options. Seriously thinking about trying it.

Sadly, both the STM32 and PIC32 these use are somewhat hard to get right now. I see more of the PIC32's in stock than the STM32's. Hence why I bought a uTerm PCB with the STM32 already installed. ?

The case I'm going to try and use for the final build has arrived! It looks like it will work and I will get to hone my 3D design and printing skills to make the brackets I need to hold things in place. Should be fun, or frustrating, or both. ?

I decided I'm going to maintain the serial connection capability, but I much prefer USB Type B connections since it's more robust and the cables are a dime a dozen. That's the adapter you see plugged into the Serial USB.

Two things I haven't decided on are...

1. Where and how to extend the GPIO. Front of the case, or back? And I'm not sure what sort of connections I'm going to use. A terminal block or a simple pin header.

2. The most important question... push button or toggle for the main power! I'm torn, but I'm leaning towards the toggle because it's more old-school.

The other buttons you see are the momentary switches that will be for "user" and "reset" on both the MBC2 and the uTerm. Of course, all the LED's will be on the front panel, as will the PS/2 keyboard connection. SD card slot will likely be on the back with the power, serial USB, and VGA.

On 10/16/2022 at 11:33 AM, Strider said:

1. Where and how to extend the GPIO. Front of the case, or back? And I'm not sure what sort of connections I'm going to use. A terminal block or a simple pin header.



2. The most important question... push button or toggle for the main power! I'm torn, but I'm leaning towards the toggle because it's more old-school.



The other buttons you see are the momentary switches that will be for "user" and "reset" on both the MBC2 and the uTerm. Of course, all the LED's will be on the front panel, as will the PS/2 keyboard connection. SD card slot will likely be on the back with the power, serial USB, and VGA.

The physical locations should be guided by how often you will be using the port. Keyboard connectors in the back seem generally better as you don't plug one in/out frequently. SD slots in the back doesn't seem wise to me, I prefer then to be easily accessible.



Go with a toggle switch - it easily indicates what the power status is at any time (unless the smoke has been released ?)

As for the GPIO, I'd suggest a pin header as you can build a cable to got to a breadboard or a terminal block, or use either as the project evolves. 

 

On 10/16/2022 at 2:52 PM, Edmond D said:

The physical locations should be guided by how often you will be using the port. Keyboard connectors in the back seem generally better as you don't plug one in/out frequently. SD slots in the back doesn't seem wise to me, I prefer then to be easily accessible.



Go with a toggle switch - it easily indicates what the power status is at any time (unless the smoke has been released ?)



As for the GPIO, I'd suggest a pin header as you can build a cable to got to a breadboard or a terminal block, or use either as the project evolves. 



 

The PS/2 is going on front for two reasons, the most important being this wont be setup 24/7, it will get moved around a lot, so the keyboard will get unplugged quite a bit. Less importantly, it just makes it easier since that's where it's located on the uTerm.

The SD card is going around back mainly because I really don't swap it out much, very rarely in fact. Once you have everything you want copied on there, not much reason to swap it out that often. Still, I may move it to the front, I'll see once I actually sit down and do the internal layout, we'll see.

For the GPIO, I'm heavily leaning toward that very option. I can put together a custom ribbon cable and block easily. ?

 

The internal support structure and front panel decal are coming along nicely I think. ?

On 8/24/2022 at 9:59 PM, Tatwi said:

The X16 is over-engineered, "too much" really. There's something to be said about a ZX Spectrum with a faster CPU, more RAM, and SD card storage - Would it be amazing? No. Does it need to be? No!

Most ARM microcontrollers these days is like an 1980s 16-bit computer on steroids minus the graphics. Which is in essence just ONE chip. And the cost is accordingly.

Ballpark CPU 48 MHz, Flashmemory 256 kB, RAM 64 kB for 2$. Secondary storage via SD-cards using the MMC mode. Keyboard via PS/2 level converted to 3.3 V.

Monochrome video can possibly be had with DMA driven SPI output or a simple CPLD as a line buffer.

On 9/15/2022 at 3:50 PM, EMwhite said:

On the edge of this topic, what software is the 'killer app' for CP/M?

VisiCalc/Lotus123 ? ?

On 10/20/2022 at 10:04 PM, Strider said:

Wow! This front panel is very cool!

Will it be printed on transparent decal?

On 10/21/2022 at 2:06 AM, Cyber said:

Wow! This front panel is very cool!



Will it be printed on transparent decal?

Oh, seconded!!

The "Z80 inside" is a really nice touch.

Thanks!

@Cyber The first print will be on a white adhesive vinyl sheet, it's what I have and use in many other projects. However I am looking into some clear vinyl sheets that will print good on our printer and not run or smear during printing.

On Sunday I'll be printing the internal supports, about 5 hours total print time, so I hope I got it all done correctly. ?

One change I was forced to make due to space limitations is the PS/2 port will no longer be extended to the front panel, but I'll be using a PS/2 to USB  adapter internally and the USB end will be on the front panel. In short, it will be front panel USB instead of PS/2. Moving the PS/2 port would have been a pain, and ugly, short of having a custom PCB made just for the port. So this is a simple solution, and since USB keyboards are vastly more common, works out better anyway.

Is that an active adapter, or one that relies on the keyboard having PS/2 fallback?