| ??? 08/18/04 00:00 Read: times Msg Score: +1 +1 Informative |
#76067 - RE: 9-bit Multiprocessor mode Responding to: ???'s previous message |
Erik said:
RS-232 was never intended for multinode. Oleg Sergeev said:
Indeed, but UART has possibility to be used for multiprocessor communications (9-bit UART with TB8/RB8 bits). Yes, but that's an entirely different matter! You cannot use the RS232 physical transceivers in a multi-node network because RS232 is specifically a point-to-point connection with absolutely NO provision in the standard for the necessary bus structure. Sure, you can bodge it by using transceivers with a shutdown mode - but then you're no longer strictly RS232. Don't get me wrong: I think the 9-bit multiprocessor mode is great - and have frequently recommended it here (see link below) - but you cannot do it on pure RS232 hardware. Oleg Sergeev said:
There are derivatives which support individual/broadcast address detection as well. To be precise, they support the address recognition in hardware - so there is absolutely no software overhead at all from messages addressed to other nodes! This is known as the Enhanced UART: http://www.8052.com/forum/read.phtml?id=69214 |
| Topic | Author | Date |
| Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
| RE: Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
| RE: Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
| RE: Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
| RE: Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
| RE: Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
| RE: Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
| RE: Multiple RS232 devices with one AT89c52 | 01/01/70 00:00 | |
RE: 9-bit Multiprocessor mode | 01/01/70 00:00 |