I am a server. I want to know which function in BSP can let me know how many clients have connected me. I am a novice and I hope to get the answer.
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I downloaded FreeRTOS port for STM32F4-Discovery from https://github.com/wangyeee/STM32F4-FreeRTOS and I managed to compile it and flash it to the board, but I don't know what to do next. I would like to verify that it is working.
I tried to use debugger and I saw that after reset the program is in function deregister_tm_clones and the board does nothing.
What to do next?
Thanks
Vaclav
You have the code, so can look to see what it is doing. Alternatively you can ask the author of the code by contacting them via github - if you do that they will see the question, if you post a question about there code here then it is unlikely they will see it.
Alternatively there are lots of resources available on the web to help you. For example there is an (old) documented port to that chip on the FreeRTOS website here: https://www.freertos.org/FreeRTOS-for-STM32F4xx-Cortex-M4F-IAR.html ST's STM32Cube software will create FreeRTOS projects for you http://www.st.com/en/development-tools/stm32cubemx.html - and if you just want to learn FreeRTOS you can download a free book here https://www.freertos.org/Documentation/RTOS_book.html
I've an issue with my current micropython project on my ESP8266. I've a 10x10 LED matrix which i would like to control via 4 shift registers.
In general 3 pins are required for the controlling DATA, LATCH and CLOCK. After some hours of internet searching the most promising solution was the usage of SPI, where also found some useful instructions for the pyboard (thank you for the code btw):
https://forum.micropython.org/viewtopic.php?t=1219
I tried to replace the pyboard specific librarys with the general machine module for the ESP8266 to get access to the SPI class. It worked fine till a specific point but the main issue at the moment is that it was not capable provide a binary signal at the DATA pin.
To be honest I'm a little bit confused about the write methods in the machine.SPI class. The docu says the return value is None. So in general what is the purpose of a write method with a return value of None (sry for the maybe silly question)
Is there maybe another solution to get a binary signal out of the data pin? I'm not sure anymore if the usage of SPI is the best way to manage the controlling. Do you have some other examples or tutorials to get deeper into the topic?
Thank you for your kind response in advance,
BR charlzo
I have a requirement where I need to connect to a POS printer from a Java Swing App.
What I came to know that there's a standard called Java POS to achieve this.
Now the problem is on java POS website (http://www.javapos.com/) I did not find anything that is helpful in getting me started.
I checked Java POS simulators (https://code.google.com/p/pos-device-simulator) but the thing is, even if I start that successfully I get no clue what to do, how to test any code against these simulators.
Can someone guide me in the right direction? Where to begin my quest about using Java POS connect to a POS Printer and then print some data successfully?
I just started on the same quest and I think that the best way to do is to grab yourself a receipt printer from a well-known vendor such as Epson or Star Micronics. They normally provide enough documentation on to get started on the whole process. The device simulator is too complex and seems to be a bit buggy in my opinion.
Assuming that you managed to get yourself a printer, here's you'll need to do:
Generate a jpos.xml containing device specific information. The vendor should have a program which can generate this information for you.
Modify the jpos.properties under $jpos.jar/jpos/res to point it to the location of your jpos.xml. Note: Your vendor tool may do this automatically for you.
Add all the necessary libraries
Start on the sample codes provided by your vendor
The somewhat incomplete documentation of JavaPOS can be found as part of the UPOS documentation in Appendix B located at http://www.nrf-arts.org/content/unifiedpos
Also, the latest programming guide on JavaPOS that I found is here.
Hope this helps.
"I wonder when JavaPOS was written as a standard, why it was not considered to implement a Printer query mechanism so that one could just query the underlying system registry and find any conneccted JavaPos device. Do you have any idea how to do the above? I don't think it's implemented. For end user running a utility to generate a jpos.xml and then modify the files/cofniguration does not make any sense to me. – Alam Sher Sep 22 at 8:21 "
Generally on Pos system, peripherals are connected to serial ports and are not declared in os (microsoft, linux, ires ...). In many pos system, constructor provide their own implementation and tools for javapos (like ibm, toshiba ... http://www-01.ibm.com/support/docview.wss?uid=pos1R4000014) to help you to discover wich device is connected and build your jpos.xml.
I'm nxj beginner.
I have some questions about bluetooth communication between PC and brick.
First, when bluetooth communication occurs, where is the birthplace processing this datas?
In other words, I want to know whether these datas will be processed on CPU or brick.
Second, what is exact roles CPU and brick in bluethooth communication?
That means what is processed on CPU and what is processed on brick.
I have searched almost web site but I can't find this anywhere.
Please help me. Thanks.
You can see it in the package structure.
lejos.nxt.*
This package contains classes running on the NXT-brick. All code in this package will be compiled for the brick and will run on the brick.
lejos.pc.*
Here the difference is not that clear. This is java-code you compile for personal computer. So most code runs on your computer. But some classes (e.g: RemoteMotorController) only send messages to the NXT-brick which gives commands to the motors.
lejos.pc.comm provides API's that allow you to communicate/control the nxt robot from the PC.
When importing the the libs to an Android project, it allows you to build an instance of the same environment used on a pc, but within android.
I agree it can be tough finding some things out. It would be great if there was as stronger lejos presence on SO
This question is months old and has remained un-answered I actually have a lot of questions about it myself, but I might be able to provide some insight for utter novices.
when using bluetooth with Android and NXJ robots, you use either lejos.pc.comm or lejos.NXJ.
Both provide APi's to do almost the same thing, but work a little differently. I don't know nearly enough about the NXJ api, but I do know that it is the one that lets you manipulate the robot much more effectively, such as outputting data to it's LCD screen, which you can't do with the pc.comm api
As far as I can tell, the pc.comm API uses both Android Bluetooth API's and it's own protocols to allow communication with Lego LCP commands.
(I want to come back to this, but I'm writing a dissert on the topic so I'll try to update it in a couple of days. Seems not many are interested though, shame)
Really hoping someone here will be able to help me. I am wanting to automate my applications and Open Office.
Can anyone point me in the correct direction? There is mountains of information out there for Microsoft Office Automation but barely anything on Open Office.
I hope someone can recommend a good set of components to purchase or perhaps some good libraries to include in my projects that will make automation easier.
Any help would be appreciated!
Kind Regards
Donovan
There are quite a lot examples around. In the UNO OpenOffice Project, there are some samples also for Delphi. The samples for other languages are also helpfull, because the systematic of UNO (which is the API of OpenOffice also over COM) is a bit complicated.
There is also a forum with some Delphi-Code: http://www.oooforum.org/forum/
There are some Tools and Constanst and Example Units, this is a very good starting point: http://www.koders.com/delphi/fidB69083385CA27692654E24A4FBC81ED2AC516B49.aspx?s=ftp#L63
I have quite a lot of code for that task, but it is too much to post it here (sorry) and it is included in a very big application.
you can start by checking out the UNO OpenOffice automation project: http://udk.openoffice.org/
There was also a Sun Microsystems initiative called ODF Toolkit, but it never took off.