rtos for 8051

This is a side issue, but I really don't buy this comment:
the correct statement would be "it can NOT do since no 8051 microprocessor core running at more than 1500MHz exist".

Both Intel and AMD are processing more than one instruction/clock cycle at higher frequencies. And the x86 instructions are not easier to process than the '51 instructions. With duplication of the tiny execution units, such a processor could use speculative evaluation to avoid stalls on misspredicted branches.

The problem is not if a GHz '51 core can be made - the problem is that the I/O pins would not work too well at 5V or 3.3V logic with such frequencies.

To make it worth the investment, and at the same practical, the core would have to be integrated into an application chip, allowing it to run all I/O at 1.2 to 1.8V. With 5V outputs supporting several mA each and full speed toggling, the chip would probably start to glow if put in a tight loop toggling all pins.

This is a side issue, but I really don't buy this comment:
the correct statement would be "it can NOT do since no 8051 microprocessor core running at more than 1500MHz exist".

Both Intel and AMD are processing more than one instruction/clock cycle at higher frequencies. And the x86 instructions are not easier to process than the '51 instructions. With duplication of the tiny execution units, such a processor could use speculative evaluation to avoid stalls on misspredicted branches.

The problem is not if a GHz '51 core can be made - the problem is that the I/O pins would not work too well at 5V or 3.3V logic with such frequencies.

To make it worth the investment, and at the same practical, the core would have to be integrated into an application chip, allowing it to run all I/O at 1.2 to 1.8V. With 5V outputs supporting several mA each and full speed toggling, the chip would probably start to glow if put in a tight loop toggling all pins.

the original statement:
it can do.... but youve got to use a 8051 microprocessor core running at more than 1500MHz

BULL!!!

the correct statement would be "it can NOT do since no 8051 microprocessor core running at more than 1500MHz exist".

Andy Neil Posted

I stand by my earlier assertion that, In general, applications that are suitable for implementation on an 8051 do not need an RTOS - but that is quite a bit different from just calling it unqualified BULL...

I stand by my statement, stating that something "can do" something if a nonexisting device were available, is BULL. If something requires something nonexisting to do somathing it can NOT do it.

The qualified 'BULL' referred to that specific phrase.

Erik

As a software developer, you should notice that the "You can do xx if yy..." in a previous post is a valid sentence, and not automatically bull because of the lack of existing 1.5GHz '51 processors. That's the nice thing about qualified conditionals :)

If the sentence had said "You can do xx [now]" it would have been bull unless such a core had existed.

The question here is if 1.5GHz is enough or how much "more than 1500MHz" that would be required.

The question here is if 1.5GHz is enough or how much "more than 1500MHz" that would be required
just for ease let us make the orignal statement 1.2Ghz making the instruction cycle frequency 100MHZ ~10nS. That would give (for a 100ns task switch) 10 instruction cucles to save the stack in XRAM, restore the new tasks stack, switch task etc. Evwn with a one clocker (120 instruction cycles) I doubt very much it could be done.

so my estimate

a whole lot more

Erik

Maybe the guy pushing his real (sorry, rapid) time operating system is expecting us to emulate an 8051 running at 1500MHz on a PC quad core running at 4MHz or more?

PC quad core running at 4MHz...

Whoops, I think I should have typed 4GHz!

I was thinking about the new hip trend in embedded systems: Z80Quad :)