Spin, Propeller, and MCUs

[Iggy]

I've been studying the idea of using MCUs to emulate older computers or as substitutes for glue and I/O circuitry.
 
Right now one of my favorites is the Parallax Propeller.
http://www.parallax.com/propeller/
 
Its a 75-100MHz 8 core 32bit MCU.
Each core acts as a 'cog', has video generation capability, and is seperately programmable.
 
So far, users have programmed the Propeller to do useful things like generate VGA signals, interpret PS/2 keyboard and mouse input, and emulate a SID chip.
 
Currently, a group of developers is working to emulate a C64.
 
I'd like to work with this chip alone AND combined with older CPUs (like the 6809, 6309, 68K, and Coldfire).
 
This is the board I'm starting with:
http://www.mikronauts.com/morpheus/
 
Dual Propellers and enhanced memory.
 
My first project will add a 63C09E, some static RAM, an SD card reader, and a serial port to the system.
 
I'd like to incorporate dual SID emulation as well.
 
Eventual the Morphues board will support a 256x192 256 color screen mode with sprites.
 
It already supports much higher resolutions (although with fewer colors).
 
I can program the Morpheus with Parallax's own Spin under Morpheus' built in OS Largos.
 
So, eventually, I hope to have a system that will marry the 6309 specific NitrosOS9 operating system with some very capable MCU hardware and software.
 
What do you think?

[Iggy]

I don't know where you guys got the idea that the Prop1 runs at 12MHz.
The internal clock is multiplied from the external clock (you might want to check out Parallax's own website rather then referencing incorrect info from somewhere else).
It actually runs at 75MHz and has been overclocked on some boards from between 80 to 100MHz.
 
Here's one board I'm looking at right now that works at 100MHz.
 
http://www.mikronauts.com/propcade/

[Iggy]

I have a TI M4 MCU on order.
So I can see the ARM arguement.
Bt your missing the point.
The Propeller is very flexible and is great for emulating other devices or implenting I/O.
 
I intend to interface it with other processors so memory is not a problem.
 
With one $8.00 chip I'll have dual SIDs, VGA, and PS2 mouse and keyboard interfaces.
 
And have you checked out the dual Prop Morpheus?
The second CPU is used primarily for video and has an optional 512K memory board.
The designer is currently working on a memory expansion for the primary CPU.
 
I can do things with the Prop that would require a lot more work with another CPU.
 
And there's a 40 pin DIP version so I can build my own hardware without having to solder surface mount components.
 
This is more about what I can do on my own.
 
I can't build my own system with ARM.

[Iggy]

You might not know this but breadboards can't go much above 50 mhz. That prop in dip format will have limitations on a breadboard or it at least should. That is why a lot of the boards are soldered.
 
You are also running overhead on the chip and that SID emulator belongs to someone.
 
You need either the st link or jtag to program Arm. My jtag to usb connector by olimex was 50 dollars. There exists a free toolchain.
 
I left the Parallex forums. I started there and I realized that unless you know what is involved, you can go down a lot of bunny trails. They sent me something like two or three power supplies till I got the right one. I should probably sell my Demo board from them because it isn't something I will invest my time in.

Interesting opinions.
Actually, I don't do breadboards and never have.
I use 2 layer PCBs.
And, yes, those have some of the same limitations, but I know about crosstalk and how to limit the trace length of high speed circuits and haven't run into a problem while working at four times the speed you quote.
 
As to the SID code, the author has no problem allowing it to be used (as do many Prop developers).
 
You speak from a position of prejudice. I'm using both ARM and Prop based devices and I wouldn't use one where the other was better suited.

[Iggy]

M4 Cheap?
Damned right.
Prop can't touch this.
 
https://estore.ti.com/Stellaris-LaunchPad.aspx
 
Ordered one a few days ago.
But I personally find ARM harder to works with (which seems to be the opposite of many of you).
 
So...moving ahead with the Prop.