Fwd: Re: [DIYbio] Re: Automation flow

[John Griessen]

Here's something to think about for a cube-spawn line of machines
instead of ethernet -- CAN bus, (Controller Area Network).
We could take a PIC as on the UBW boards,
http://ww1.microchip.com/downloads/en/devicedoc/39887b.pdf

which is 8 bit and super low power (like MSP430), and with 8x8 hardware multiplier
to do motor controlling, and add a CAN chip so cubes can be daisy chained,
which is one of James's design goal wants.

One package is PIC18F4458-I/PT with a streaming parallel port that might make CAN bus
chip interface easier for $5.21 ($4.3 in 100's).


-------- Original Message --------
To: John Griessen <jo...@industromatic.com>

You're working on outdated info (don't worry not alone).

Go to microchip.com and download mplab-x. It is gcc and netbeans based,
runs on linux os/x win. C compiler is free.
- if you haven't found this, then you haven't really been looking...
Go to microchip and buy a PICKit 3 (programmer/debugger), $30. cross
platform with mplab-x.
Go to sparkfun and buy a ubw ($25) which plugs into computer with USB
cable. it accepts serial commands for pin control.
Get a USB cable, $1.
Go to the ubw site and download the source code for ubw which includes
mplab project for rebuilding.
I now have an entire eng dept and qa dept at my day job using UBW's like
crazy for all kinds of things, straight from sparkfun. Some of the
usage runs stock ubw firmware, some usage we just completely customize
the ubw firmware but leave the command processing (usb serial port stuff).

Note it is easier to just get a cheap winXP PC laptop to burn the pic's
with and connect to scopes and such, it is a better development setup
anyway to work on one machine and use another machine as a lab bench
set, and you won't find good usb-logic analyzers for linux or os/x
period. Attempting embedded development on linux is just a lame waste
of time when the goal is to get things done.

If using win, then UBW has a windows app which allows burning the part
directly from USB (uses UBW's bootloader). No need for a microchip
programmer thus saves 15-30 seconds per comple/download/test step which
makes writing/debugging a lot faster. very handy to use the UBW
firmware burner app.. (actually it's a microchip app, that UBW reuses
without any mods).

The UBW is $25 at sparkfun but really only costs half that (or less?) to
make. If you build them yourself it would be $10 I guess. My eng
office doesn't even bother, it's cheaper in terms of effort to just buy
30 of them from sparkfun. UBW doesn't have an OS and an OS isn't
needed.. it just processes commands and uses simple timers. Works great.

BTW my eng office recently started using this USB logic analyzer like
crazy (bought like 15 of them they were so useful, everyone wanted
one). It's simple but... very very fast for development and very large
memory. also multiplatform. http://www.saleae.com/logic/

Using the above, for under $200 there is an entire product development
setup. In 1990's this would have cost $20,000.

For the rest (ie. network bridge), just use Raspberry pi. It is more
expensive and complex and overkill etc etc. but the marketing hype
alone (by association with that project) will make it worth it.


## Jonathan Cline
## jcl...@ieee.org
## Mobile: +1-805-617-0223
########################



On 3/2/13 9:18 PM, John Griessen wrote:
> On 03/02/2013 10:01 PM, Jonathan Cline wrote:
>> I think the future is in USB peripherals
> .
> .
> .
> Move the user interface onto the PC or tablet or smart phone and let
>> the lab device just be completely enclosed. The devices themselves
>> should have no more than 2 push buttons which covers the
>> operations of: power toggle and "go/stop"; and no more than 2 LED's
>> to indicate operational status. That's old-school getter-done
>> design.
>
> I've been resisting, but your logic is getting to me.
>
> You've recommended PICs as "must have's" for value, so I'll be
> figuring how to run a KVM or something
> to have a Win XP in an easily maintained virtual machine to run PIC
> Axe and such with.
> I haven't found any unix/linux based PIC development method.

[John Griessen]

On 03/03/2013 09:33 AM, John Griessen wrote:
> Here's something to think about for a cube-spawn line of machines
> instead of ethernet -- CAN bus, (Controller Area Network).
> We could take a PIC as on the UBW boards,
> http://ww1.microchip.com/downloads/en/devicedoc/39887b.pdf
>
> which is 8 bit and super low power (like MSP430), and with 8x8 hardware multiplier
> to do motor controlling, and add a CAN chip so cubes can be daisy chained,
> which is one of James's design goal wants.

http://datasheet.octopart.com/SN65HVDA1050AQDRQ1-Texas-Instruments-datasheet-10298090.pdf

is a $0.56 part with Bus-Fault Protection of –27 V to 40 V and
High Electromagnetic Compliance (EMC) so it does not need a CAN bus "protector" added.

[John Griessen]

To make a system with a microcontroller you also usually by a chip that encapsulates
the bit timing logic of the CAN protocol, like:

http://octopart.com/mcp2515-i%2Fso-microchip-430187 which costs $1.98 $1.38 in 100's.