1394 servo and RIO

We are replacing a 1394 controller and I am trying to decipher the RIO side of the controlling PLC (SLC) I am at a loss as to how the addresses of the PLC 1747-SN inputs and outputs of the SLC align with the relevant Ri's and Ro's of the 1394 controller. There seems to be no correlation in the addresses!! That is to say that the first say eight inputs at the 1394 and eight outputs of the PLC are no where near each other.
Any help appreciated.

pauly said:

I am at a loss as to how the addresses of the PLC 1747-SN inputs and outputs of the SLC align with the relevant Ri's and Ro's of the 1394 controller. There seems to be no correlation in the addresses!! That is to say that the first say eight inputs at the 1394 and eight outputs of the PLC are no where near each other.
Any help appreciated.

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It's been a while since I've worked with the 1747-SN, so please help me & others out with a little more info:
- Is bit 0, etc. for the SLC still bit 0 for the drive? Are they in the same order?
- What addresses are being used in the SLC for the drive I/O?
- What rack, group is the drive located at? What size rack?
- Are there any block transfers to/from the drive or just discrete I/O?

The SN module is designed to handle up to 4 racks of I/O, as I recall. I've not worked with the 1394, but it's RIO that is coming into play.

I can be confusing when you're using a RIO emulating device like a 1394 or a PanelView. That device only knows its own chunk of I/O data, which is going to start at 0. Where that chunk starts in the SLC-500 depends on how that 1747-SN and the RIO adapter are set up.

The 1747-SN has 32 words of Input data and 32 words of Output data for its Slot.

For a 1747-SN in Slot 5, for example, these would be data tables I:5.0 through I:5.31 and O:5.0 through O:5.31.

The servo's discrete I/O data will be somewhere in that table. The offset is determined by the Rack Number and Starting Group.

It gets more complex when you start using Block Transfers, since the programmer is entirely responsible for where she gets and puts the data blocks for those.

Excel spreadsheets are your friend. Start documenting all of your settings any block transfers. Once you make a few spreadsheets pointing back and forth between stuff it gets a whole lot easier