How to share RS232 paralley?

[andres90125]

right this way. to suggest this circuit MAX3322, now the problem is that is not what is normally a PCI card as normal output of a PC, unless you do a power booster and repeater right through this and from there you depart for your communication , is also an option

---------- Post added at 16:46 ---------- Previous post was at 16:15 ----------

then. if you were to use 232, with 16 devices can suppose that distance between each? and as an RS232 network to behave interference present?
If we place a booster as suggested MAX3322, because the current PCI cards or current PC does not have the ability to withstand such a load current,
why not make a direct USB converter> 485 taking the energy from the USB port itself. And place a device 485 for each micro terminal having the option and advantage so you know that the potential for interference WILL maintained by the kind of communication gap 485 and the distances and speeds will more easily be managed

 

[FvM]

I don't understand what you are exactly talking about. Multi-drop RS232 devices driven by a standard PC RS232 interface are used in existing products and working well. I also can't follow your considerations about problems with MAX3322. It's not intended as a booster, rather than as a replacement for MAX232 with additional features.

I don't however feel responsible for promoting this solution. It's just one of many available options.

 

[bluehole]

@andres90125 There are some restriction ( self imposed ) for RS485 .... Firstly I use Development boards available locally , They don't have RS485 interface but Most of them have RS232 interface. Secondly If i consider Using RS485 then I have to use 13 ( 12 boards + 1 PC) RS232->RS485 converter.

@tpetar Is right and RS485 is most suitable for this kind of application, and from the images he posted I Understood i have to connect RS485 coonverter at each RS232 port on my setup. well in a future project I may consider such a configuration. Because of the budget.

@FvM Please throw some more light on Multidrop RS232 and How to boost the powerlevel of RS232 so that 12 Listner can easily read.

 

[FvM]

The RS232 multi-drop solutions I referred to are using higher receiver impedance to increase the fan out with a standard RS232 driver. These drivers are designed to drive a single receiver with specified voltage levels, including a considerable margin above minimum required receiver levels. Paralleling receivers reduces the margin and would be a step towards "operation by accident", as andres90125 mentioned. Thus I won't suggest it.

 

[bluehole]

Well ... then there is no way for RS232 based broadcast kind of thing even if I need only one way communication from host to clients???

Lets assume there are several RF RS232 TXRs available. If I need one way communication from Host to Client only can the RF RS232 TXRs will be of any help???

 

[bluehole]

Hi all,
Any other thought on this subject? or wireless RS232 half duplex .... any thing ...

pleae I help I am in the middle of nowhere...

 

[andres90125]

Xbee can use if you are looking for wireless is very good immunity to interference from other systems, wifi etc. etc. can work encrypted. and a channel search systems free or less interfered by the host of very good quality. I implement it in a draft of a host PC automotive alignment and four read heads of sensors in the vehicle, excellent performance