Need Block Transfer for 1746-NO4V?

Hi,

Just want to ask those experience user, do I need BT for 1746-NO4V or any 4 channel analog module for slc 500 in a RIO setup using 1-slot addressing?

Thanks.

Regards,
CK Chew

Can you please tell us more about your set up.

Are you using a 1747-SN scanner module with a 1747-ASB in the remote chassis??

If this is true then the 1746-NO4V module can be addressed either using BT or with Discrete I/O. This is selected with SW3-7 on the ASB modules.

If you have only one analog module in the remote chassis, then Discrete I/O may work fine and requires no extra programming in the SLC, but it does take up more words in the I/O image. Specifically the 1746-N04V will take up 4 words of Output image in the 1747-SN scanner.

The advantage of BT mode is that it only uses up one byte of the I/O image....but it requires more programming and the SN module will only transfer one BT per I/O scan. So if you have say five analog modules in the remote chassis, they will only be updated once every five I/O scans. (This might be perfectly fast enough for your application.)

Philip,

I'm running 1747-BSN in my local rack. In my local rack I've a pair of hot-back SLC 5/04.

In my remote rack I've this 1746-NO4V. I'm using 1-slot addressing. Require BT right?

Hi,

As I explained above you can do this with either BT ...OR discrete I/O image.

Which one you choose depends on how much spare I/O image you have in the 1747-SN/B scanner.

If you have plenty of spare I/O image then I suggest you use discrete I/O image transfer.

If there is not any spare I/O then use the BT.

All this is explained in Ch 3 of the 1747-ASB manual. It has all the details you need.