Thank all

But I need sample code for read.

Almost ,all documents use write code and I didn't saw read code.


On Saturday, April 24, 2021 at 10:58:36 AM UTC+4:30 vasile wrote:

> Majid, one good practice when you're testing communication between two 
> embedded systems (A and B) is to check each one with a terminal first. 
>
> Assuming A is sending to B and B receives and does something on IO port, 
> test first the TX of A to the computer terminal, then RX of B from the 
> computer terminal. After that, only if each one works ok, connect TX/RX of 
> A with B.  Some good free terminals for this job (search for:) Realterm, 
> Teraterm, Termite. You may also need a hardware converter which depends on 
> your computer (if you have a real COM port with RS232 levels or just an 
> USB/RS232 with 3.3V or 5V levels). 
>                              
> This approach will protect you from a lot of trouble and make you 
> understand if a byte, a word, an ASCII or something else is truly 
> sent/received and was sent/received in the right order. 
>
> Simplify your work by sending and receiving ASCII symbols first and then 
> understand 
> all the used procedures from the libraries (this is mandatory to understand 
> which is your fault/misunderstanding or which is the software bug... 
> there are bugs in any software...:) ).
>
>
> On Sat, Apr 24, 2021 at 8:36 AM Rob CJ <[email protected]> wrote:
>
>> Hi Majid,
>>
>> If you want to send an integer value you indeed have to send it in bytes. 
>> But that thouls be faily easy with JAL.
>>
>> If have for example a variable of type word you can do the following
>>
>> var word my_word_variable
>> var byte  my_byte_variable_low at my_word_variable
>> var byte my_byte_high at my_word_variable + 1
>>
>> You can then send both 'my_byte' variables separately and in the other 
>> PIC you do the same, read the two bytes which are mapped to a word.
>>
>> Als see the documentation of the JAL compiler.
>>
>> Kind regards,
>>
>> Rob
>>
>> ------------------------------
>> *Van:* [email protected] <[email protected]> namens majid 
>> ebru <[email protected]>
>> *Verzonden:* vrijdag 23 april 2021 19:47
>> *Aan:* jallib <[email protected]>
>> *Onderwerp:* Re: NT: [jallib] How to send & receive data over medium 
>> distance 
>>  
>>
>> Please help me 
>>
>> I almost work with micro ,12 years ago .
>>
>> Now I can't send / receive data?!
>>
>> I should send and receive an integer(like adv value and ....) , but in 
>> serial_sw_data I just can send a byte ?!?!!!
>> And just read a byte with serial_sw_read(char)?!
>>
>> I know that my kowlage about electronic is wake , but now I should do 
>> read&write data?!
>>
>> Please guide me,🙏🙏🙏🙏🙏🙏🙏🙏
>>
>> On Thursday, April 22, 2021 at 11:23:23 PM UTC+4:30 [email protected] 
>> wrote:
>>
>> Hi Majid,
>>
>> You have to provide more information. How do you know that they stopped? 
>> Did you narrow down the code down to the minimal size to show that it 
>> fails? If so you can share that code.
>>
>> And to answer your other - not posted - comment. Due to the fact that you 
>> use this group to answer trivial questions that you can find on the 
>> Internet (which you should not do) and which are specific JAL or PIC 
>> related, your posts are now moderated. Only posts which are relevant to 
>> this group are passed on to the other group members.
>>
>> Kind regards,
>>
>> Rob
>>
>> ------------------------------
>> *Van:* [email protected] <[email protected]> namens majid 
>> ebru <[email protected]>
>> *Verzonden:* donderdag 22 april 2021 20:19
>>
>> *Aan:* jallib <[email protected]>
>> *Onderwerp:* Re: NT: [jallib] How to send & receive data over medium 
>> distance
>> Hi  
>>
>> Please help me again😢😢😫😫🥺🥺🤔🤔
>>
>> When I connected two PICs together , everything is ok.
>>
>> But when disconnect port serial , both PICs hanged ?!?!
>>
>> Both micro stoped , and when connected again ,both micro work correctly?!
>>
>> In fact both micro stopped in line : if  serial_sw_read(char)) then block 
>> ....
>>
>> And doesn't run other codes🤔🥺😫😢
>>
>> Why?!
>>
>> How should I do ?!
>> On Wednesday, April 21, 2021 at 10:12:03 PM UTC+4:30 funlw65(Vasi) wrote:
>>
>> The microcontroller boards that are used in Polish Universities are all 
>> equipped with (external - note for Majid) RS485 chips.  
>>
>> On Wed, Apr 21, 2021 at 4:54 PM Rob CJ <[email protected]> wrote:
>>
>> Hi Majid,
>>
>> Please use Google to find out what RS485 and IIC is. Use the Jallib group 
>> for issues with libraries and the compiler not for general questions that 
>> you can easily find on the internet.
>>
>> Thanks.
>>
>> Kind regards,
>>
>> Rob
>>
>> ------------------------------
>> *Van:* [email protected] <[email protected]> namens majid 
>> ebru <[email protected]>
>> *Verzonden:* woensdag 21 april 2021 15:47
>> *Aan:* jallib <[email protected]>
>> *Onderwerp:* Re: NT: [jallib] How to send & receive data over medium 
>> distance 
>>  
>> RS485 is very powerful. 
>>
>> But I don't how to implement in PIC?!?
>>
>> Is i2c the same rs485?!
>>
>> On Wednesday, April 21, 2021 at 4:41:19 PM UTC+4:30 vasile wrote:
>>
>> At 15m and 5V there is no problem with data sent in current. Using 
>> twisted wire cable is a good habit. 
>> From the EMI perspective twisted cable it is about half as good as a 
>> shielded cable and has the parasitic capacity quite low compared with the 
>> shielded cable.
>> RS485 (standard 32 loads) is feasible at 1Km and quite high speed. Still 
>> there is an issue with the ground line and requires good terminators.
>> Data goes either on A&B plus ground cable (three wires between Tx and RX) 
>> or just A&B (two wire cable) and ground connected to earth on the 
>> transmitter and receiver end. 
>> In the last configuration an issue is quite frequent caused by an offset 
>> (variable ground potential between TX and RX).
>> Also lightning is a problem for outdoor cables...and nothing help... 
>> :)... no matter how others will convince you to put three tranzorbs on each 
>> TX and RX  end.
>> happy communications! 
>>
>>
>> On Wed, Apr 21, 2021 at 8:32 AM 'Oliver Seitz' via jallib <
>> [email protected]> wrote:
>>
>> Thanks for the additional information, 800m is something very different 
>> from 20m ;-)
>>
>> I can imagine that 20m at 5V ground-referenced is doable, but when you're 
>> starting, better stick to the specifications and try your luck when you 
>> have a bit of experience.
>>
>> I myself am at a similar project, like 15 meter, and I want to use as 
>> little standby current as possible, and no twisted pairs. It's 
>> uni-directional, with constant-current pullup at the receiver and optically 
>> isolated pulldown at the sender with 1200 baud... First test of the concept 
>> in a few days ;-)
>>
>> If standby current was of no concern, I'd use RS422 or RS485 
>> drivers/receivers, true RS232 is old-fashioned and needs to many components.
>>
>>
>> Greets,
>> Kiste
>>
>> Am Mittwoch, 21. April 2021, 07:02:46 MESZ hat vsurducan <
>> [email protected]> Folgendes geschrieben: 
>>
>>
>>
>>
>>
>> Oliver, I remember the problems I had with an EIA232 with +/-8V output 
>> running at 800m at 9600bps. Everything works until due the transceiver 
>> heating the voltage dropped at +/-7.6V...:)
>> The length is given by the voltage at the level converter of the 
>> transmitter output. All level converters with charge pumps are not able to 
>> give more than +/-8V...+/-10V in the happiest circumstances.
>> Oldest/goldest EIA232 worked at +/-25V up to 2km.
>> For 20m you do noy need any level converter at the output of your PIC, 
>> just a twisted pair RX-GND TX-GND (CAT5 ethernet cable is perfect) and an 
>> open collector transmitter ( a gate) with pull-up resistor in the receiver 
>> end (at 20m distance from the transmitter).
>> However Majid,  I think you need first to learn jal and for that there is 
>> a learning curve which has to be passed....
>> Please start with the examples, compile them, make them run, modify them 
>> as you wish and post only when nothing works for you after three days of 
>> trying...this will help you more than you may believe right now...
>> best wishes
>>
>> On Wed, Apr 21, 2021 at 7:28 AM 'Oliver Seitz' via jallib <
>> [email protected]> wrote:
>> > Hi Majid,
>> > 
>> > SPI is designed for centimeters, I don't think it can work reliably 
>> over 20 meters.
>> > 
>> > RS232 at 9600 baud is ok for 150 meters, if you're using real RS232 
>> drivers and receivers like from the MAX232 series. The PIC controller does 
>> not have RS232, it has a usart which handles the NRZ protocol. This 
>> protocol is best known as being used by the RS232 interface. Therefore the 
>> protocol itself is commonly (but wrongly) referred to as "RS232"
>> > 
>> > RS232 uses negative voltages as a symbolic "1" and positive voltages 
>> for "0". At the receiving side, the voltage must at least go higher than 
>> +3V for "0" and lower than -3V for "1". At the sending side, voltages from 
>> up to +15V and down to -15V are used.
>> > 
>> > So, to answer your question in two simple sentences: RS232 is ok for 
>> the job. But RS232 is not what comes out of the controller.
>> > 
>> > Greets,
>> > Kiste
>> > 
>> > 
>> > 
>> > 
>> > Am Dienstag, 20. April 2021, 21:56:34 MESZ hat majid ebru <
>> [email protected]> Folgendes geschrieben: 
>> > 
>> > 
>> > 
>> > 
>> > 
>> > can i ask another  question??
>> > 
>> > if it is 20 meter distance between PICs , i should use RS232 or SPI?
>> > 
>> > so sorry and thanks a lot
>> > 
>> > ‪majid ebru‬‏ در تاریخ سه‌شنبه ۲۰ آوریل ۲۰۲۱ ساعت 
>> > 
>> > -- 
>> > You received this message because you are subscribed to the Google 
>> Groups "jallib" group.
>> > To unsubscribe from this group and stop receiving emails from it, send 
>> an email to [email protected].
>> > To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/1697687282.4677348.1618979276333%40mail.yahoo.com
>> .
>> > 
>>
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "jallib" group.
>> To unsubscribe from this group and stop receiving emails from it, send an 
>> email to [email protected].
>> To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/CAM%2Bj4qtaBjojssk_HHFK1M2dhhL9CNNf3mygd1F3nH0B5bck9A%40mail.gmail.com
>> .
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "jallib" group.
>> To unsubscribe from this group and stop receiving emails from it, send an 
>> email to [email protected].
>>
>> To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/1020737915.4719521.1618983169979%40mail.yahoo.com
>> .
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "jallib" group.
>> To unsubscribe from this group and stop receiving emails from it, send an 
>> email to [email protected].
>> To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/22c899b2-b475-404d-9982-fb4e9ffe3169n%40googlegroups.com
>>  
>> <https://groups.google.com/d/msgid/jallib/22c899b2-b475-404d-9982-fb4e9ffe3169n%40googlegroups.com?utm_medium=email&utm_source=footer>
>> .
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "jallib" group.
>> To unsubscribe from this group and stop receiving emails from it, send an 
>> email to [email protected].
>>
>> To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/AM0PR07MB624188EEE1255C4E45C31F80E6479%40AM0PR07MB6241.eurprd07.prod.outlook.com
>>  
>> <https://groups.google.com/d/msgid/jallib/AM0PR07MB624188EEE1255C4E45C31F80E6479%40AM0PR07MB6241.eurprd07.prod.outlook.com?utm_medium=email&utm_source=footer>
>> .
>>
>>
>>
>> -- 
>> Vasi
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "jallib" group.
>> To unsubscribe from this group and stop receiving emails from it, send an 
>> email to [email protected].
>> To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/ad446bf9-5eab-4168-8326-b33f2a02c0f5n%40googlegroups.com
>>  
>> <https://groups.google.com/d/msgid/jallib/ad446bf9-5eab-4168-8326-b33f2a02c0f5n%40googlegroups.com?utm_medium=email&utm_source=footer>
>> .
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "jallib" group.
>> To unsubscribe from this group and stop receiving emails from it, send an 
>> email to [email protected].
>> To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/187dbbf2-8c1b-43c2-ac9b-ce320495f60fn%40googlegroups.com
>>  
>> <https://groups.google.com/d/msgid/jallib/187dbbf2-8c1b-43c2-ac9b-ce320495f60fn%40googlegroups.com?utm_medium=email&utm_source=footer>
>> .
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "jallib" group.
>> To unsubscribe from this group and stop receiving emails from it, send an 
>> email to [email protected].
>>
> To view this discussion on the web visit 
>> https://groups.google.com/d/msgid/jallib/AM0PR07MB6241CB67E4CBAE8CFD01D0D0E6449%40AM0PR07MB6241.eurprd07.prod.outlook.com
>>  
>> <https://groups.google.com/d/msgid/jallib/AM0PR07MB6241CB67E4CBAE8CFD01D0D0E6449%40AM0PR07MB6241.eurprd07.prod.outlook.com?utm_medium=email&utm_source=footer>
>> .
>>
>

-- 
You received this message because you are subscribed to the Google Groups 
"jallib" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/jallib/b32a5de8-117c-4c73-a771-5ba9a493b45cn%40googlegroups.com.

Reply via email to