1771-asb compatibility with the 1756-dhrio

Which versions of the 1771-ASB module are compatible with the 1756-DHRIO? Will versions A and B work?

Publication 1756-UM514B-EN-P - February 2003 indicates that A and B will work if a 150 ohm resistor is used.​

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Table 8.3
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Determining Resistor Rating and the Number of Devices Connected on Your Network
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If your remote I/O network: Use thisresistor rating:
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1771-ASB/A 150 ohm
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1771-ASB/B 150 ohm​

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We are using RSlogix 5000 version 15.​

Any other Ideas?

I think the reason you haven't got any responses is that you asked a very specific question that you seemed to already have the answer for. The table you mention specifically calls out the series A and B modules. I would interpret this to mean they will work within the limitations mentioned. (i.e. 57K or 155K, 16 devices max)

I think you would get more responses if you would provide some context. What are you trying to do? I can guess that you might be upgrading an old PLC-2 to a ControlLogix, but that's just a guess. The older ASB modules may have additional limitations. I seem to remember that they could only do 2-slot addressing.

More info = more potential help.

Any series of 1771-ASB will work with a 1756-DHRIO scanner.

The 1771-ASB Series C added 230.4 kb/s data rate and "extended node" mode in 1991. You won't have those features, 1/2 slot addressing, or 32-point module support in Series A and B adapters.

But otherwise they are electrically and protocol-wise compatible with the 1756-DHRIO.