Can anyone help me find a way to make a PC talk to a whole bunch of uC chips. I have built a RS232 - RS485/RS422 converter. I want to use the "serial address mode" of the '51 (Pic has it too) to reduce sw overhead.
It basically uses a 1 start, 8 data, 1 parity and 1 stop bit. To address a uC, you set parity to 1. All uC get a serial interupt when they receive that, check if they are adressed and if so change a setting to be interupted by all incoming bytes.
My problem is to handle sending from the PC. I need to set parity to 1 (mark) for the first byte in a message, then reset it to 0 (space) for the rest. I XP you never know when the data is sent and waste a lot of time waiting to make sure it is all gone. There is a replacement XP driver (Nielsen) out there, but I do not have the cash for it. Any other ideas?
The PC is the only master in the system and will only receive data in the data mode when it asks for it.
Hope you can help
Andre
It basically uses a 1 start, 8 data, 1 parity and 1 stop bit. To address a uC, you set parity to 1. All uC get a serial interupt when they receive that, check if they are adressed and if so change a setting to be interupted by all incoming bytes.
My problem is to handle sending from the PC. I need to set parity to 1 (mark) for the first byte in a message, then reset it to 0 (space) for the rest. I XP you never know when the data is sent and waste a lot of time waiting to make sure it is all gone. There is a replacement XP driver (Nielsen) out there, but I do not have the cash for it. Any other ideas?
The PC is the only master in the system and will only receive data in the data mode when it asks for it.
Hope you can help
Andre