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  1. HellasTechn

    RS422 to RS232 converter.

    Yes. I know that the ic's are the best and probably the only way to go (for ttl output). I am new to this so i do need guidance. could you provide me with the datasheet for the dual input rs422 chip ? it looks like i cant find any. (uA/MC9637). I would like to proceed with a high quality chip...
  2. HellasTechn

    RS422 to RS232 converter.

    Do they provide rs232 (-12V - +12V) ? or TTL (0V - +5V) ? I understand... I am not sure. 4800 BPS about 30 meters. one rs422 and one rs232 (microcontroller). I think i should have provided the diagram in post 1. Sorry ! In the diagram below, the red line is what i was thinking to try...
  3. HellasTechn

    Serial communication problem.

    Ho my god... I was not aware that the hurricane was called irma. Actually it didnt even crossed my mind that he may have been affected. My best wishes to you sir Chris !
  4. HellasTechn

    WACOM Cintiq 21UX - LCD issue

    If the problem is one of the CCFL lamps snand you can not find a replacement then you could convert it to LED backlight. Usually when CCFL fail the symptom is that the backlight comes on and goes off one second later.
  5. HellasTechn

    Serial communication problem.

    Yes i am positive. I have them on a "mount" so i justremoved the 2n2222 and put the bc547 the same direction. I also made sure the transistors where well sit in place.
  6. HellasTechn

    Serial communication problem.

    I do not understand :(
  7. HellasTechn

    RS422 to RS232 converter.

    My concern is that since i need TTL signals in the first place then why not just use the signal on line B instead of building the circuit that will give me a -5V to +5v rs232 ? First chance i get, i will use the Oscope and check the rs422 lines to see if they really are as shown in the picture...
  8. HellasTechn

    RS422 to RS232 converter.

    The concept is the same but the project is different. I had an rs232 transmitter that i needed converted to TTL to supply a Microcontroller. Now i have an rs422 transmitter that i need to convert it to TTL to supply the same type microcontroller. Only in this case the problem is that the...
  9. HellasTechn

    RS422 to RS232 converter.

    OK. i have an rs232 transmitter and an rs232receiver. The receiver is not supposed to send anything back to the transmitter. Only "listen"...
  10. HellasTechn

    RS422 to RS232 converter.

    Iam not sure... i can not read the picture. its too small. I dont understand the bi directional.
  11. HellasTechn

    RS422 to RS232 converter.

    after searching i came across this http://www.bb-elec.com/Learning-Center/All-White-Papers/Serial/%E2%80%A2-Polarities-for-Differential-Pair-Signals-(RS-422.aspx judging by the picture i would say that the rs422 B line is identical to the rs232 TTL line. could i cust use the B line ground...
  12. HellasTechn

    RS422 to RS232 converter.

    Here i should say that i can use either TTL level rs232 like the one used by UART or hardware rs232 signals that are then converted to TTL level with the transistor inverter circuit.
  13. HellasTechn

    RS422 to RS232 converter.

    What do you mean switch ar rs232 levels ? could you explain more please ? or could you make a diagram ?
  14. HellasTechn

    RS422 to RS232 converter.

    Good day ! I have been searching the net for some cheap RS422 to RS232 converter. While i have found tons of RS232 to RS422 converters, i have found none to do the opposite. Anyone have an idea where i can find one or a circuit diagram i could use to build one ? Thank You !
  15. HellasTechn

    PCB building

    One more Board.
  16. HellasTechn

    Battery charger questions

    It could be due to the fact that lead accid batteryes that stay over discharged for too long may become what i call "decapitated" messed up internally. Im not sure. just guessing. Dorke's explanation makes more sence though.
  17. HellasTechn

    Turning LG smart tv off on the mains

    I am quite sure it is not more dangerous than leaving it pluged in 24/7. In other words, i beleave it is.
  18. HellasTechn

    Serial communication problem.

    Good day to you all friends ! The last few days i have been working on my picaxe project. I have designed a new PCB and descided to implement the circuit shown in post #61 for the Picaxe to receive rs232. After i finished the board i started running tests to see if all are working correctly. I...
  19. HellasTechn

    Serial communication problem.

    Thats normal since on the Oscope picture the far right pulse is the first to have occured (on the timeline). Also i think its called LSB meaning less significant bit but Less significant digit is not wrong also.
  20. HellasTechn

    Serial communication problem.

    Yes. Right.. here is where i am confused. So to transmit the word 0101 the rs232 waveform should look like this (without start-stop bits). Is that correct ? Reading back through the posts i think i am getting the picture now. Like with telegraph key mentioned in post #46 P.S. Sir chris you...
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