Hello Dears

What could be the reason for using 32 registers for a card with 16 digital inputs?

this is a digital input card from the stahl brand and used for profibus.

Best regards

Hello and thank you for your reply

32 bit and  single i/o card

This isn't a Siemens product.

Take a look at attached PDF file.

By 32-bit registers and 16-DI, is each DI associated with its own 32-bit register (a Modbus term?).

If you mean the telegram associated with this specific (non-Siemens) Stahl-branded16-DI module has 1 DWord (32-bits) for each DI, yes, that is rather wasteful.

However, if you mean a single 32-bit DWord has all 16-bits, why not a 16-bit Word?

My guess is the people creating the firmware and the Profibus interface people could not agree within the required delivery time constraints on how to make it work for a 16-bit word and already had something functional that used 32-bit data.

Or, they had a specific methodology that they could use 2 DI's together as 1 32-bit DWord via Profibus, so if you only use 1 16-bit DI, you still get the 1 32-bit DWord.

Just guesses.  Ask Stahl's customer support on their web site / support forums if you want a real answer.

saeednejati

Hello Dears

What could be the reason for using 32 registers for a card with 16 digital inputs?

this is a digital input card from the stahl brand and used for profibus.

Best regards