8051/2051 help, please

However, do you know what is pla? strictly speaking its not belong to memory chip but a logical function chip.

are you going to programming this pla with 8051?

you can program 8086 which is more comp;lex than 8051. one is 16bit one is 8bit.

but 8051 is a microchip or say it integrate all required periphery, but 8086 is not, only a cpu.

suggest you use 89c51, whih has memory inside. it has 4k or 6k 15 upto 32k depend on your need.

of cause you can link pla as periphery to complete a special function. but we used to use gal device.

good good study.

well then, i believe i won't require an external ROM for 8951 is it? but i would still like to know what kind of PLA or ROM chip i could have used wit 8051, i really wanna know. pls elaborate a bit more on diffrence between 8051 and 8086, i kno 8086 is a 16bit CPU, but 8051 could have acted like an early cpu with other peripheral devices connected to it before 8086 was built, isn't it?(i'm not sure)

Dunno about 8051...

But there are plenty of microcontroller with enough on board RAM for such a simple task.
You can store 4 of your 2bit binary numbers in eack 8 bit byte, so you only need 250 bytes of ram. If you need it to be non volatile memory then you should an a small EEPROM.

Del

ok, can you name any one of those? or advice me on a suitable EEPROM chip? i need an external memory coz i don't wanna complicate the programming by having to perform operations on a byte to extract 2 bits at a time from it, unless the instruction set of the controller has anyting in it to make the task easy....

I use the Zilog Z86series of chips Z86E04 is a small one, up to the Z86733.
type 1kx8bit serial eeprom into google.

Getting the micro to talk to a serial EEPROM is MUCH more difficult than a simple bit of bit manipulation.
Any micro can manipulate bits..
e.g To extract the two most significant bits from a byte copy the byte to a suitable location (I usually have some working locations which I call things like 'scrap' 'scrap1' etc.

Then 'and' scrap with C0 hex, manipulate your bits.
Do this for your 4 pairs of bits then 'or' them back together and stick 'em back where you got 'em from.

Much quicker than talking to a serial EE... trust me...I'm an engineer
Del

alright thanx a lot for the info, really appreciate it. i just hope Z86E04 is available here. by the way, do you kno of a method of building a digital clock that is accurate enough for months at a time? the only easy method that comes to my mind is using an astable multivibrator calibrated for a pulse of 1sec coupled to an up counter(pls excuse me for going off topic).

I'd think you can build a clock from any micro' just use a 'watch crystal' to get the right frequency...

BTw you need a developmend kit for any micro you use... Zilog do a board which will emulatre and program the ZX86 series...the program is blown into the chip's OTP (one time programable) memory.

Maybe a family of chips which can be preprogrammed might be better for you? ST do some of them... or the PIC family have cheap readilly available development kits...
Del

Look at the Microchip family. They have all flavors of microcontrollers with internal program memory and cheap development boards. You will be able to download your program in the chip within a day or two if you have any talent for the job.

Hi Amsung2

It has been a while (198x) and by now I am mixing 8051 /8085 /8x86 / PIC / Zilog / Motorola knowledge.

Google for Intel 8051 - for accurate info.