8051-class "learner" board - is it worth making one?
Robot Groups | Search | About
User Password
Register Now! Lost Password?
 comp.robotics.misc    Post an article   get this group's latest topics as an RSS feed add this group's latest topics to your My MSN content add this group's latest topics to your My Yahoo content
Subject Author Date
8051-class "learner" board - is it worth making one? zwsdotcom 05-11-2006
Posted by on May 11, 2006, 7:31 pm
Please log in for more thread options
This is a crosspost from comp.arch.embedded, with some enhancement.

The story:
I semi-accidentally acquired a fairly large quantity of surplus ROMless
8051-class parts in DIP-40 packages. These include Intel and Signetics
8031, 8032, and lots of Dallas DS80C310 and DS80C320. Along with them
came a bunch of 6264 and 62256 SRAMs.

Somewhere in my archives I have a layout for a board that takes a
DIP-40 8031 and has 32K of program flash and either 2K, 8K or 32K of
RAM. It also has a level-shifted serial port, and some miscellaneous
headers for GPIOs and such.

In this day and age, is it worth my while to do a production run of
these boards and offer them for sale to get rid of the surplus chips? I
would write a small bootloader and preload that into flash so you
wouldn't need additional hardware to load code onto the board.

I figure I could [afford to] sell an assembled board for ~USD35.

When I posted the above in c.a.e I got some suggestions, including to
ask the question again here.

Is that old design of mine even useful as it is, or would I have to
build something more exotic to make it interesting?


Posted by pogo on May 11, 2006, 7:53 pm
Please log in for more thread options
> This is a crosspost from comp.arch.embedded, with some
enhancement.
>
> The story:
> I semi-accidentally acquired a fairly large quantity of surplus
ROMless
> 8051-class parts in DIP-40 packages. These include Intel and
Signetics
> 8031, 8032, and lots of Dallas DS80C310 and DS80C320. Along with
them
> came a bunch of 6264 and 62256 SRAMs.
>
> Somewhere in my archives I have a layout for a board that takes a
> DIP-40 8031 and has 32K of program flash and either 2K, 8K or 32K
of
> RAM. It also has a level-shifted serial port, and some
miscellaneous
> headers for GPIOs and such.
>
> In this day and age, is it worth my while to do a production run
of
> these boards and offer them for sale to get rid of the surplus
chips? I
> would write a small bootloader and preload that into flash so you
> wouldn't need additional hardware to load code onto the board.
>
> I figure I could [afford to] sell an assembled board for ~USD35.
>
> When I posted the above in c.a.e I got some suggestions,
including to
> ask the question again here.
>
> Is that old design of mine even useful as it is, or would I have
to
> build something more exotic to make it interesting?

Personally, I would offer the chips for sale on eBay or something
like that to see what you could unload. You could add a note at the
bottom of the auction ad asking people to email you with any
interest in the production run board.

On the other hand, if you just want to create a product that you
think is useful and better than others, I say go for it! Kind of a
personal decision ...

JCD



Posted by Jeff Shirley on May 12, 2006, 6:28 pm
Please log in for more thread options
In comp.robotics.misc zwsdotcom@gmail.com wrote:
> This is a crosspost from comp.arch.embedded, with some enhancement.

> The story:
> I semi-accidentally acquired a fairly large quantity of surplus ROMless
> 8051-class parts in DIP-40 packages. These include Intel and Signetics
> 8031, 8032, and lots of Dallas DS80C310 and DS80C320. Along with them
> came a bunch of 6264 and 62256 SRAMs.

> Somewhere in my archives I have a layout for a board that takes a
> DIP-40 8031 and has 32K of program flash and either 2K, 8K or 32K of
> RAM. It also has a level-shifted serial port, and some miscellaneous
> headers for GPIOs and such.

> In this day and age, is it worth my while to do a production run of
> these boards and offer them for sale to get rid of the surplus chips? I
> would write a small bootloader and preload that into flash so you
> wouldn't need additional hardware to load code onto the board.

> I figure I could [afford to] sell an assembled board for ~USD35.

> When I posted the above in c.a.e I got some suggestions, including to
> ask the question again here.

> Is that old design of mine even useful as it is, or would I have to
> build something more exotic to make it interesting?

Hi.

I have a shelf full of 8051 boards and chips, which is probably why I am the
only one in my club using 25-year-old technology in a robot. I wanted a board
with a serial boot loader, where I did not have to re-vector the interrupts
from the boot loader. I designed a small board that ANDed PSEN and RD, and
used a TTL signal to swap between the boot loader (EPROM) and RAM at location
0x0000. That way I can load code, toggle the signal, reset and run the code
from RAM.

I did finally find a handful of boards I could modify to work this way, and
used them instead of my own design. It was also nice that these boards had
a hook for a memory mapped device (8255, quadrature decoder, etc.), and could
support a few different RAM and EPROM sizes.

I am not sure how much of a market there is for "vintage" 8051 boards. I am
in the process of porting some of my stuff to ARM, and have started to really
appreciate the newer 8051-core offerings from companies like Atmel and Analog
Devices. The extra peripherals are great, and it is nice not to have to use
I/O ports for external memory. I might still be a customer if you go ahead
with the project, and your board supports code developed with SDCC. I would
probably be more inclined to buy bare boards, however, and then probably only
two or three.

Jeff.
--
Jeff Shirley
spamzilla@mindspring.com
"Bill Gates is filthy rich, but that doesn't mean I want to be married to him."

Posted by Randy M. Dumse on May 14, 2006, 12:09 pm
Please log in for more thread options
> I semi-accidentally acquired a fairly large quantity of surplus
> ROMless 8051-class parts in DIP-40 packages.

I purposely bought 30K of them in PLCC to offer a cheap 8051 board. That
was like 10 years ago. They're mostly still here.

> I figure I could [afford to] sell an assembled board for ~USD35.

We sold/sell them at $39. We've offered specials at $29. They don't move
very well. Probably our best documented boards, with many options for
language.

So my opinion is the only way I'm going to move this inventory of 8051's
is to design some little comsumer product that doesn't require much
smarts, and sell them embedded in it. Even that is iffy, because the
glue logic to go with the IC and larger board to hold it all costs as
much as an ARM now.

--
Randy M. Dumse
www.newmicros.com
Caution: Objects in mirror are more confused than they appear.



Posted by on May 14, 2006, 12:13 pm
Please log in for more thread options

Randy M. Dumse wrote:

> > I semi-accidentally acquired a fairly large quantity of surplus
> > ROMless 8051-class parts in DIP-40 packages.
>
> I purposely bought 30K of them in PLCC to offer a cheap 8051 board. That
> was like 10 years ago. They're mostly still here.

This is what I was afraid of. Thanks for the response.


Similar ThreadsPosted
learner from african heritage August 17, 2007, 8:49 pm
extensive learner near the offence August 22, 2007, 6:27 am
learner in the light of whole diminishs simultaneously August 16, 2007, 4:32 am
hi i m making a robotic arm September 4, 2006, 5:12 am
Re: Making you understand September 17, 2007, 5:48 am
Re: Making you understand September 17, 2007, 1:41 pm
Re: Making you understand September 17, 2007, 3:36 pm
Don't try to run a decision-making! December 8, 2007, 9:59 pm
grid per careful making August 17, 2007, 3:17 pm
Re: Making a kitty into a bagpipe December 29, 2007, 5:28 pm

The site map in XML format XML site map
 other useful resources:
Official Robosapien Website
Lego Mindstorms Website

Contact Us | Privacy Policy