RCA CDP1802 – as 2013 version

Probably the first 8Bit CMOS Processor,

introduced about  1976


But how would a time warp of 37 years from 1976 to 2013 affect performance?

Hardware description languages like VHDL and Verilog can describe functionality for hardware for implementation into FPGA and ASIC.

Having the processor in VHDL allows for easy implementation into an FPGA – or even as ASIC using today’s technology.

And we are in the process of just doing this.


Some Links:


Wikipedia always gives a good overview
http://en.wikipedia.org/wiki/RCA_1802


This processor is now manufactured by Intersil, for High-Rel only
http://www.intersil.com/en/products/space-and-harsh-environment/harsh-environment/microprocessors-and-peripherals/CDP1802A.html


This user manual describes its function very well
http://datasheets.chipdb.org/RCA/MPM-201B_CDP1802_Users_Manual_Nov77.pdf


The BPM802 Design Ideas Book, written at the time, gives some background and collects info to easily get started, published in 1980, scanned in recently by the author, start with page 4
http://www.exemark.com/Microcontrollers/BMP802.pdf


There was an RCA Microtutor 2 Kit, the original manual we still have to get access to to scan it in, until now we only have the German version, see
http://www.exemark.com/Microcontrollers/Microtutor2web.pdf
 

 

The Popular Electronics ELF was a Kit to build a low cost system, compiled from the web
http://www.exemark.com/Microcontrollers/PopularElecwebc.pdf


Much more information you can find under
www.cosmacelf.com


Tom Pittman shows you how to program this little beast
http://www.cosmacelf.com/shortcourse.htm


Try it out online, 7A 7B 30 00 to let the q output flash the Q output

http://www.donnelly-house.net/programming/cdp1802/simelf/

 

If you are looking for an emulator in SW, see
http://www.cosmacelf.com/links.htm

 

See as well Lee Hart’s Kit, available now
http://www.retrotechnology.com/memship/memship.html

 

Or Spare Time Gizmos’ Kit with a 137 page manual including schematics at
http://www.sparetimegizmos.com/Hardware/Elf2K.htm

 

 There is a user group
http://dir.groups.yahoo.com/group/cosmacelf/message/9780

 

Look at the layout of the 1802 chip, and you can print it even as large poster
http://www.visual6502.org/images/pages/RCA_1802.html

 

This is just a link collection we have chosen – there are many more.
Send them and we might add them in.

 

 

For now everybody is using existing CDP1802s,
manufactured in the same technology as 1976
or actually manufactured then.

 

 

Now to our own FPGA implementation:

There is a licence to be signed if you want to have access to the VHDL.
Soon to be downloadable from

www.exemark.com

 

It all started with Scott L Baker, who has written a VHDL implementation of the 1802. He kindly agreed to give us access to the VHDL for hobby usage. He is available for commercial work.

 

Using the Lattice XO2 series of FPGAs with on-board Flash and RAM adds as well ROM, RAM, IO on the same chip to the processor functionality, so no additional parts really needed and you have a complete microcomputer.

http://www.latticesemi.com/products/cpld/machxo2/index.cfm

 

There are 2 low cost boards available, the Pico board and Breakout board, so no hardware has to be built.

http://www.latticesemi.com/products/cpld/machxo2/machxo2evaluationboardsde.cfm

 

You can download the free Diamond Design Software from Lattice, just sign up and go

http://www.latticesemi.com/products/designsoftware/diamond/index.cfm

 

Porting this design/implementation later to other FPGA families will be easy, as no special functions are used. (RAM and Flash might have to be added externally), FPGA suppliers this could be put onto are

Achronix
http://www.achronix.com/

Atmel  
http://www.atmel.com/products/other/field_programmable_gate_array/default.aspx

 

Altera
http://www.altera.co.uk/

 

Lattice
http://www.latticesemi.co.uk/products/fpga/index.cfm

 

Microsemi / Actel
http://www.actel.com/

 

Tabula
https://www.tabula.com/

 

Xilinx
http://www.xilinx.com/products/silicon-devices/fpga/index.htm

 


We are looking at increasing the 1802TIMEWARPTEAM with people who would like to have a bit of fun and contribute. Please send an email to epldfpga@aol.com and tell us how you would like to help.

 

Phase 1 would be concentrating on the first Lattice implementation, core, RAM, ROM, peripherals

 

Phase 2 then to port to other platforms

 

Phase 3 tbd.

 

There are other variants like CDP1803, 1804, 1805 and 1806, basically variants with some additions

 

This page is work in progress, it will change as it grows 

02 February 2013