1-Wire Network Emulation over RS485
I'd like to create software for some Atmegas that will emulate a 1-wire network however the actual communication will occur over RS485. The goal is to allow software written for 1-wire hardware to function with this custom hardware. It will emulate 3 devices a 1-wire Master (DS2480b/ds9097u) a DS2450S (4 Channel ADC) and a DS2408 (8 channel general IO). Again the goal is for software written for 1-wire to think it's communicating with a 1-wire master and DS2408 and DS2450s devices.
Master based on Atmega164p (1 serial port connects to MAx232 and other serial port to a MAX485 or similar chip)
Slaves run on Atmega48 with max485 chip.
I maybe making this sound more complicated then it is. 1-wire software sends commands over the serial port to the master, the master then communicates commands to the slaves and relays the response back over the serial port connection.
Additional Project Description:
05/11/2013 at 5:21 IST
One thing to add...All of the features do not need to be implemented. We just need to be able to get ADC readings and set/clear the outputs. Overdrive etc need not be implemented.
05/12/2013 at 9:04 IST
To further clarify. 3 software programs need to be written.
1. Atmega164p will emulate a DS2480b 1-wire serial master. The Atmega164p has two serial ports, one will attach to a pc through max232 and the other will communicate through a RS485 line driver to the slaves (described below) on the network. There are a handful of commands for the ds2480b. The goal is for 1-wire software (such as OneWireViewer) to think it's communicating with a DS2480b
2. Atmega48 will emulate a DS2450S 1-wire 4 channel ADC. It will respond to the same commands as a real DS2450s but the communication will occur through the uart over the RS485 network. Software such as Onewireviewer will see it as a DS2450s (when attached to the master described above).
3. Atmega48 will emulate a DS2408 1-wire 8 channel general IO. It will respond to the same commands as a real DS2408 but the communication will occur through the uart over the RS485 network. Software such as Onewireviewer will see it as a DS2408 (when attached to the master described above.)
Those are the 3 software programs that need to be written. I have the hardware done and can provide hardware for testing to the chosen worker.