Hi all,
I am using RCM3100 core module to read a serial number ibutton (DS1990A) using serial port B via DS2450 adapter. It works fine for a while and quits occasionally. Whenever it quits, DS2450 stops recognizing the DS1990A at the ibutton reader but it continues to provide response to the Rabbit’s reset pulse (issued once a second to see if any slave devices are preset at the reader), making it harder for me to know when DS2450 really locked up. Only the user knows that it stopped working as he is not getting any authorization feedback LED’s. The only viable soultion at this point to make it work is to reset power to the DS2450 card!! I cant figure whether this problem is on Rabbit’s side or on DS2450 side?
Does any one faced this?? Please let me know if you have any ideas…
Thank you
I2C
[QUOTE=i2cRabbit;2583]Hi all,
I am using RCM3100 core module to read a serial number ibutton (DS1990A) using serial port B via DS2450 adapter.
Does any one faced this?? Please let me know if you have any ideas…
[/quote]
I am a bit confused as to why you are reading a DS1990A via a DS2450 which is a 4 channel AtoD Converter?
Do you mean you have the DS2450 and the DS1990A on the same 1-Wire signal line?
If so, try removing the DS2450 leaving just the iButton on the wire.
Hey LightHouseMan,
I am having problem when I tried to read using DS2480B instead of DS2450. We are using both DS2480B & DS2450 and did not pay attention during my last post.
The serial adapter DS2480B is locking up occasionally without recognizing the DS1990A device connected to it via the reader.
Any help would be great!
Thank You
In that case I suggest you use a scope to capture and debug the signal coming from the RS232<–>1-Wire converter and going to iButton.
At this stage it sounds like there is some communication problem on the 1 wire side of things, although it would be worth checking what level your RS232 lines are at when idle - if they are sitting at ‘0’ then maybe it is confusing the iButton - which might not detect the start signal correctly?