请问PIC32MZ和DMX protocol能一起使用吗？

我知道，DMX是一种使用异步串行通信的通信协议，它是单向协议，它使用EIA485差分信号，AKA RS-485，对电信号有一些限制。外围设备，仅使用TX信号，如果PIC32是控制器。EIA－48 5差分信号将需要PIC32 TX引脚和DMX布线之间的线路驱动器组件。和声提供多通道、多用户UART驱动程序。使用异步串行通信的一些通信协议，更喜欢使用自己的驱动程序代码，直接控制UART外围设备。对于DMX512协议信令，无论如何都不希望与任何其他通信协议共享UART模块。X512在250千比特/秒使用相对快速的异步信令，并且在每个包之前强制中断信号，以及每个分组的中断和第一字节之间的定时停止。min中断92微秒，最小MAB 12微秒，以及启动之间的时间。对于一个数据包的中断，下一个分组的中断信号的开始至少为1204微秒。这些时序要求可以通过使用UART UART驱动程序来实现，但是我不依赖于没有测试的情况。迈西尔



      以下为原文

    Hi,
I have not done anything like that.
As I understand, DMX is a communication protocol using Asynchronous Serial communication,
in a one way protocol.
It use EIA-485 differential signaling, aka RS-485, with some restrictins for electrical signals.
In PIC32MX or MZ that is done using the ordinary UART peripheral, using TX signal only, if the PIC32 is Controller.
EIA-485 differential signaling will require a line driver component between PIC32 TX pin and DMX wiring.
 
Harmony provide a multi-channel, multi-user UART driver.
Using the Harmony UART driver with a specific Communication Protocol, may sometimes be tricky.
Some communication protocols using asynchronous serial communication, rather prefer to use their own driver code, controlling the UART peripheral directly. 
 
For DMX512 protocol signaling, you are not likely to want to share a UART module with any other communication protocol anyway.
DMX512 use relatively fast asynchronous signaling at 250 kbits/s,
and have some specific signaling requirements, in mandatory Break signal before each package,
and a Timed  Stop between the break and first byte of each packet.
Min Break 92 microseconds, minimum MAB 12 microseconds, and time between start of Break for one packet, and start of Break signal for the next packet minimum 1204 microseconds.
 
These timing requirements may be fulfilled by chance using Harmony UART driver, but I would not rely upon that without testing.
 
   Mysil

是的，这是可以做到的。您需要使用RS485收发器与RTS用作传输使能。生成独特的“破绽”就是诀窍。我不能发布代码，因为它是“为某人”。



      以下为原文

    Yes, it can be done.  You need to use an RS485 transceiver with RTS used as a transmit enable.  Generating the unique 'break' is the trick.  I can't post code as it was 'for someone'.

我已经用一个Max（48）来转换信号，它工作。现在我有问题来正确配置UART。我已经把一个波特率设置为250000和8N2。但是接收到的数据并不像预期的那样。通常第一个字节应该是0x7e，而我的日志中从来没有看到这个字节。



      以下为原文

    I've put a max485 to convert the signal and it works.
Now I've problems to configure the UART correctly .
I've put a baudrate at 250000 and 8N2 . but the data received don't look as expected.
Normally the first byte should be a 0x7E and I never see this byte on my log.
I there a special UART config for the DMX

你似乎没有提到，如果你正在制作一个DMX主机（=发送器）或奴隶（=接收器）。



      以下为原文

    You don't seem to mention if you are making a DMX master (=transmitter) or slave (=receiver).
 

你为什么期望看到这个？它不在DMX标准中。



      以下为原文

   


Why are you expecting to see that? It isn't in the DMX standard.

它是DMX从站。是的，是DMX标准，但是当我指定波特＝250000和8n2时，我接收的数据是不正确的。



      以下为原文

    It is a DMX Slave.
Yes it is the DMX standart but when I specify baud =250000 and 8N2 the data I receive are not correct.
 

对不起，我犯了一个错误，这是在这里的C代码，它是一个USB / DMX转换器的代码，我认为它是协议，但它只是USB /转换器的协议。所以现在我不知道到底应该看什么。



      以下为原文

    Sorry I've made a mistake it is in the c# code takenhere
and it is the code for a USB/DMX converter and I tought it was the protocol, but it is only the protocol for the USB/converter.
So now I don't know exactly what I should see .

有一个迷恋形式的人忘记了在C中，从零开始的数字被视为八进制格式。当你只到“004”时不要紧，但是如果你试图使用“010”，就很容易把你绊倒。



      以下为原文

   
Someone with a fetish for formatting has forgotten that in C, numbers starting with zero are treated as octal format.
Doesn't matter when you only go up to "004", but could easily trip you up if you tried to use "010".
 

DMX帧以一个中断开始，这是12个或更多比特周期的零。UART通常将此视为0x00的数据，以及由于停止位为0而不是1的帧错误，所以我没有使用PIC32为DMX，所以不能确切地告诉它如何对中断作出反应。接着是开始代码，这是一个字节，对于正常的DMX总是0x00。然后每个信道遵循一个字节，控制器不需要发送所有512个信道，只要它们只支持少量的信道。然后，序列与下一帧重复，帧之间可能有延迟，但在规范中不需要。我强烈推荐阅读“MXX512的推荐实践：用户和安装程序指南”，它可以从http://tSP.esta.org/tsp/d.…ts/PuffISHOD.DOX.PHP下载，它是从列表底部的一个-您需要在网站上注册，但我相信它仍然可以自由地进行。虽然该文档不是实际的规范，但它包含了足够的技术信息来实现DMX接收器，并且也相当容易阅读。



      以下为原文

   
The DMX frame begins with a break, which is a zero for 12 or more bit periods. UARTs will typically see this as data of 0x00 along with a framing error due to the stop bit being 0 instead of 1, I haven't used a PIC32 for DMX so can't tell you exactly how it reacts to the break. This is followed by the start code, this is one byte and for normal DMX is always 0x00. There then follows one byte per channel, controllers don't bother to send all 512 channels if they onlysupport a smaller number of them. The sequence then repeats with the next frame, there may be a delay between frames but it isn't required in the specification. I would strongly reccommend reading "Recommended Practice for DMX512: A guide for users and installers", it can be downloaded from http://tsp.esta.org/tsp/d...ts/published_docs.php, it is one up from the bottom of the list - you need to register on the site but I believe it is still free to do that. Although that document isn't the actual specification it includes more that enough technical information to implement a DMX receiver, and is also considerably easier to read.

链接不起作用，因为它吸引了下面的“，”HTTP://TSP.EST.Org/TSP/Doopts/PuffISHOD.DOX.PHP



      以下为原文

    Link doesn't work because it sucked in the following ","
http://tsp.esta.org/tsp/documents/published_docs.php