I would still add an cheap intermediate box - small format box with
RS232 on USB, Ethernet, tiny disk (use SSD if the location dusty or
subject to vibration) and a couple of Gigs of RAM running Linux. Might
even be a candidate for a Raspberry Pi or one of its commercial cousins!
Does not need a screen, keyboard or mouse once setup. Just set it next
to the Digital Indicator (or attach it to the DI with double sided tape)
and plug it into the LAN or go wireless.
- isolation from changes in OFBiz - new versions, bug fixes
- isolation from OFBiz if you decide to go to another ERP
- can write a clean API that will be resistant to change on the
Weighbridge/DI side.
- easier to debug RS232 issues, reset probably easier, trace generation
- validation easier,
- can log its own audit trail if required. Got request at hh:mm, took
reading x, took picture#, sent it at hh:mm, received OFBiz conformation
of message accepted at HH:MM.
- easier to test the web service API on the box and could also be
helpful in testing the OFBiz client side (generate mock transactions)
- easier to control a webcam from a simple program rather than trying to
add camera control to OFBiz. OFBiz can get camera image anytime it is
needed in OFBiz.
OFBiz only need to know that it requires an image to be taken and what
API (Webservice? call) it has to issue to get it done.
- less customization of OFBiz and the customization should fit better
with OFBiz normal use and customization patterns.
- OFBiz can trigger the capture of current Weighbridge through API -
simple code that should be easy to inject into the POS flow.
If you do not get any other comments, you might want to describe in
detail your thoughts on the POS workflow to get some expert comment on
how your specific requirements fit into the OFBiz POS flow and how hard
it would be to inject the API calls at the correct points.
It is easier (and more fun) to criticize a detailed design than to try
to propose a design for someone else's situation. Just human nature;-)
Ron
On 19/01/2016 2:22 AM, Andrew Dent - CTCroydon wrote:
Hi Ron
The Digital Indicator is a legally calibrated device, that is matched
to the Load cells of the Weighbridge. It cannot be substituted for
something else.
The data from the Digital Indicator is raw numbers and matches the
display.
If OfBiz is not running, then the data is available in real time on
the Digital Indicator. So if the Users have to switch to a manual
process, then there is no problem.
OfBiz needs to record the realtime data only at the time that the user
processes a POS transaction. (for example a truck has driven on to the
Weighbridge and stops for measurement, and a docket printed for the
driver.)
For a POS requirement the only Weighbridge data that is important is
when the truck stops on the Weighbridge for measurement.
5 to 10 second lag is probably ok.
Though the current Access Database software displays the data in
realtime, as the RS232 data is being constantly sent from the Digital
Indicator at all times.
Ofbiz will need to trigger a Webcam to take a still photo of the truck
and its load, and store it so that it can be recalled at a later date.
But I think this is probably easier to get working than displaying the
Digital Indicator data in real time.
Another service will be required to record all the data historically
in 30 second intervals 24 hours per day, but this historical data is
not needed in OfBiz for POS or accounting requirements.
That 30 sec interval data can be piped to a different database for
other purposes.
Cheers
Andrew
------ Original Message ------
From: "Ron Wheeler" <[email protected]>
To: [email protected]
Sent: 19-1-2016 5:48:53 PM
Subject: Re: OfBiz POS for Weighbridge
You probably need a process that listens to the RS232 feed from the
Weighbridge and records data and events.
This process could have a web service that would allow OFBiz to
interrogate the process to get current status or recent events.
I would be most comfortable with a separate box to replace the
Digital Indicator with a real-time display and let the OFBiz server
ask this machine for what it needs.
- I am assuming that this process needs to be available even if OFBiz
is not running.
- The RS232 link has no protocol so it does not have any error
recovery if the listener is not able to capture the Weighbridge data
so a dedicated PC is going to make operations more comfortable than
a link to a server that IT may stop and start without regard to
operations needs.
- a warm backup unit could be kept by operations to ensure that a
failure of the main box does not shut down operations for an extended
period.
You probably need to provide some more details about what data and
events are captured and what OFBiz needs to present.
- real-time vs history
- display vs reports
- actions triggered in OFBiz by events captured from the Weighbridge
You may also want to provide some details about your thoughts on
synchronization of permanent data vs real-time display.
- allowable lag for transferring event details
- what triggers bulk data transfer - does the listener push data to
OFBiz or does OFBiz ask for data.
Ron
On 19/01/2016 12:08 AM, Andrew Dent - CTCroydon wrote:
Hi
An existing customer of ours is looking to replace their Weighbridge
software.
I haven't used or implemented the OfBiz POS module before, but for
this customer it might be a good fit.
I'm wondering if anyone else has done this, and maybe like to assist
with this project.
There are two 60 ton Weighbridges on site.
Each Weighbridge has a PC in a local building with a RS232 connected
Rinstrum 5000 Digital Indicator box
http://www.a1weighing.com.au/5000.htm
that the Load Cells of the Weighbridge terminate into.
My thoughts are that the data stream from the Rinstrum 5000 Digital
Indicator would be displayed to the user in OfBiz.
There are obviously lots of other requirements, but the data from
the RS232 is the main requirement that I do not know how to display
in realtime on the OfBiz or OfBiz POS UI.
I have a Rinstrum 5000 Digital Indicator that I can use for software
dev purposes, with some resistors arranged to pretend to be a Loadcell.
Regards
Andrew Dent
-- Ron Wheeler
President
Artifact Software Inc
email: [email protected]
skype: ronaldmwheeler
phone: 866-970-2435, ext 102
--
Ron Wheeler
President
Artifact Software Inc
email: [email protected]
skype: ronaldmwheeler
phone: 866-970-2435, ext 102
