Help me find a suitable microcontroller compatible with 80C51

[priestnot]

First hello

I am trying to find a microcontroler to suit my needs.

i need speed and i need it to be 80c51 compatible so i find DS89C450 in maxim's website.

BUT and this is a big but
i don't know if the maximum crystal for the 1 Machine Cycle -> 1 clock cycle is 33MHz.

I need to know this in order to compare it with the 89C51RD2 that has 1 Machine Cycle -> 6 clock cycle.

thanks for all the help...

 

[wek]

DS89C450 from maxim

Yes, the maximum clock frequency is 33MHz, and one instruction cycle is 1 clock, but you are trying to compare uncomparable, the number of instruction cycles per a particular instruction is different for the RD2 (which is in this respect equivalent to the original 8501).

Although a precise ratio is impossible to give because it depends on the particular instruction mix in a given program, the instruction cycle/instruction penalty is around 30-50% for all the single-clocker '51 derivatives. It means that for the same oscillator clock, the DS89C4x0 would not be 6 times as fast as the 'RD2, but only about 4-4.5 times faster.

All this is valid with purely internal code execution with internal RAM. External memories access imposes extra waitstates on the DS89C450, i.e. even slower execution.

JW

PS. It's not from Maxim, but from Dallas Semiconductor - OK they merged so it makes little difference, just for the record... ;-)

 

[priestnot]

Re: DS89C450 from maxim

Thanks for the quick reply...

So let me see if i understood what you said.


So for the 89C51RD2:

In Standard Mode:
• 60 MHz (Vcc 4.5V to 5.5V and Internal Code execution only)
• 12 clock cycles -> 1 Machine cycle
• 1 machine cycle -> 0.2µs

– In X2 mode (6 Clocks/machine cycle)
• 30 MHz (Vcc 4.5V to 5.5V and Internal Code execution only)
• 6 clock cycles -> 1 Machine cycle
• 1 machine cycle -> 0.2µs

So it means that in mode X1 and in mode X2, 1 Machine Cycle takes the same time 0.2µs.


And for the DS89C450:
In any Mode:
• 33 MHz (Vcc 4.5V to 5.5V and Internal Code execution only)
• 1 clock cycles -> 1 Machine cycle
• 1 machine cycle -> 30ηs

So in conclusion the DS89C450 is faster then the 89C51RD2

Can any one tell me if there is a faster 80c51 compatible faster then this ones?

 

[wek]

DS89C450 from maxim

What I was trying to tell is, that even if you have roughly 6x faster machine cycle in the DS89C4x0, it does not mean your program will run 6x faster, as individual instructions have different timings. For example, on the "classic" '51 (including the 'RD2), MOV A,#DATA takes 1 machine cycle, whereas on the DS89C450 it takes 2 machine cycles. Have a look at my page at http://www.efton.sk/51comp/51comp.htm for a detailed overview - the answer of your last question is there, too. That table is some 3 years old, so some of the newest chips are missing - for example the Ramtron Versa is now 40MHz singleclocker, and there are new doubleclockers from Infineon available, too (the XC8xx line).

There are many singleclockers, doubleclockers and 4-clockers out there, offering blazing speeds; but don't expect too much compatibility - only Dallas strives for pin-for-pin compatibility for example, and many of the new chips are 3V only. Also, for *all* singleclockers the machine cycle penalty I mentioned above applies.

JW

 

[memarian]

Re: DS89C450 from maxim

Hi,

About DS89C450 : I worked with previous version of this chip,DS89C420 and i'm impressed with it's performance,but you also need a good compiler (if you write your programs in C,...) for best performance (for me it was SDCC and i'm disappointed using KEIL).
if you need faster 8051 uController, you can use SILICON LABRATORIES Chips.this is their site : www.silabs.com.they have 1clock/cycle or 2clocks/cycle uControllers up to 100 MIPS (100Mega instruction per Second.)one of the advantages of their chips is JTAG(for some of them,not all),but be careful about your selection,because usually their chips have SMD Packages (QFTP,QFN,..) not DIP.

Good Luck!

 

[priestnot]

Re: DS89C450 from maxim

YUPYYYY
i found what i was looking for...

The C8051F131 from SILICON LABRATORIES will suit my needs. the package doesnt matter i can do a surface mout pcb.

I just want to know if the core is very similar to the 80c51 in instruction/execution time. If the number of Machine (instruction) cycles per a particular instruction is very different from the original 80c51????

Now that i have chosen the micro controller i need to know the best tools to development.

Witch software can i use to program it by ISP (In system programing)? And if its possible?

Witch is the best IDE for programing in C/Assembly. (i saw that keil doesn't fully support this micro controller.

Can any one recommend other software?

 

[priestnot]

Re: DS89C450 from maxim

I notice that, Silicon Laboratories has a IDE for their products, i wonder if anyone already used it. and has some idea if it works fine or it has some faults comparing with others IDE's.

I noticed also that there is also a ISP programmer software called UtillDLL.exe
and keil recommends, winburn.

And i also don't find any schematic for the ISP programmer, i think it might be the same for the 80c51RD2 from Atmel but i am not sure.

 

[lisbas]

DS89C450 from maxim

hi all

how can i a program ds89c450 to controll two motors? any body knows???


hugs

 

[priestnot]

DS89C450 from maxim

Of course. you can use any microcontroler.
you just have to make your self the PWM (pulse with modulation).
But you have to connect the motor to the microcontroler trough a driver so you can feed the motor with the rigth "voltage".