replacement for 27C64 and 80C31/8051

[gbowne1]

pins 80c31

I am designing and building a radio transmitter that works in the bands from 1,800 KHz to 30MHz.

It is based on a 10 year old design that uses a 3 chip computer using the 80C31 and a 27C64. The EPROM is supposed to have 2,008 lines of assembly code.

I am redesigning the circut so that it is not so modular. The original design was designed to be housed in a small chassis. I now have two rackmount chassis that I wish to use with the project, one 12" high and the other 6" high. They both go about 22" front to back. The design is spaced over about 7 different PC boards. I would like to either slim it down to about 3 boards or design a planar system using ISA type 8 or 16 bit bus cards.

I am intending on updating to 2006 technology.

The original design used a 2 row, 16 character per row. LCD display that is backlit. I was planning on doubling that to 4 x 32.

I need to know what I could change the controller to in the update.

I can post text files of component lists from the original design or parts of the original text.

Greg

 

[sunish]

27c64 schematics

hai
it's possible
but it's not a simple job
i had done it earlier
it willtakea lot of time to convert the source code of 8031
to the current version
you may pm me with your where abouts for more help

reg

sun

 

[CMOS]

Use AT89C52 from Atmel. It is a direct replacement to old 8051 parts with internal 8KB Flash memory.

 

[IanP]

Depending on the number of the microcontroller pins used as I/Os you can consider full 40-pin version of 8051-derivative, or, if the number is relatively low you can use 8051-reduced-pin microcontroller such as AT89C2051 (2kB FLASH program memory) .. see picture below ..
http://www.atmel.com/dyn/resources/prod_documents/doc0368.pdf

Regards,
IanP

 

[gbowne1]

thanks for your input IanP.

The 80C31 is a 40 pin processor. I believe all of the except Pin 10 through 18 are used. I have a copy of the PCB etching pattern and the schematics as well as the parts list for the controller board. Suggested was the AT89C2051 and AT89C52.

I looked at the spec for the AT89C2051.. I need the 20P3 PDIP type.

I also want to change the VCO which is a mechanica motor driven VCO as well.

The transmitter based on a double conversion superhetrodyne design.

I have no idea how much output this transmitter has but it's supposed to have at least 5W output in my notes.

Some time ago I wanted to design this around the popular 80x86 chip.. but someone mentioned to me that unless the board is well sheilded from RF, it would be a bad idea.

Greg

 

[IanP]

In the 8031/2764 configuration the microcontroller uses P0, P2, PSEN and ALE (=18 pins) just to read from the 2764 program memory .. what a waste!!! ..
From the description of the PCB it looks like you will have more than enough pins if you use the 2051 version ..

Regards,
IanP

 

[gbowne1]

I've read that some people use the PIC 16F type micros in RF desgin such at this one.

Seems like you're right IanP. I'm going to look into that one too.

Edit:

Whilest the project is underway, I thought I would add that at the very best I would like to design reverse engineer and also redesign the layout of the boards.

There are 18 such boards in the design which is WAY too many. Most of them would cost $50 to $100 each to build. I was hoping that.. I could build the design on one main board that is 12 x 7" or 8" or 9".. at the most 9-1/2".. if that doesn't happen, 12 x 12 is the max I would allow.

My thoughts is that once this design is accomplished, it could be less modular.. but more Planar. With the possibility of allowing the seperate circuits on 8 or 16 bit cards.. so that a person could remove each board for testing, repair, etc. very easily.

I was speaking with a couple friends of mine who now work as engineers in the AM and FM broadcast industry who helped design the circuits and boards used by
Trio/Kenwood and ICOM and Yeasu during the last 30-35 years. I showed them both the shematics and the etching and layout prints. They said that from what they saw, there are too many errors in the design. Most of them are wrong part #'s, missing parts, etc. Also the documents were too vague. Many of the parts are too expensive, outdated, the wrong types, unavailable, and more.

Keep in mind this is supposed to have been technology available 10-12 years ago. I would hope that in the past 10-12 years things have gotten better.

The second thing they said is that the documents were trying to make the transmitter/transceiver seem as though it is digital and "intelligent", when it is actually an analog device which is trying very hard to be digital.

My other problem is that the VCO and the optical shaft encoder used in the desgin seem to be too archaic.

The last thing that has to be addressed is the finals, the cooling via FAN and Heat Sink, the operator controls, display.

Greg