![]() The TXD signal (pin 3) drives an NPN transistor (Q1) to get the "open collector" aspect of the output side of the bus. ![]() The normal output voltage range for current USB to RS232 adaptors seems to be about -6V to +6V. The diode D1 is used to prevent the positive power supply from going negative if the DTR signal goes low. ![]() Looking at the schematic for the 9 Pin RS232 to CAT / CI-V interface, you can see that the board is powered from pin 4 (DTR), so DTR must be set high for the board to operate. Both interfaces use a similar physical layer design. The name CAT seems to be in wider usage for this purpose. ICOM calls their communication system CI-V and Yeasu calls it CAT. The design for the RS232 to CI-V adapter was shamelessly copied from, thanks!
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |