Brillohead
Member
- Join Date
- Apr 2004
- Posts
- 2
Hi. I'm new to this board, but hope someone here may be able to help me out. I have a question about the "requested word count" item in a block transfer instruction.
I actually am going to be using a 1747-SN connected to a rack with a 1747-ASB and four analog input and output cards (NI4 in slot 1, NO4I in slots 2 and 3, and an NT4 in slot 10). The other slots will have IA16 and OA16 cards and will map discretely. I plan on using 1-slot addressing. If I start at Rack 0, Group 0 (and if I understand this correctly) then I'll be using slot 0 in Group 0 for the NI4, slot 0 in Group 1 for one NO4I, slot 0 in Group 2 for the other NO4I, and slot 0 in Rack 1, Group 1 for the NT4 (the other input and output cards fill the intermediate groups).
My question is this...do I have to have individual block transfer instructions for eack group? My first thought is "yes" because I have to specify rack, group, and slot in the BTR/BTW instructions. If this is the case, then I'm assuming my "requested word count" for each BTR/BTW instruction would be 4, since these analog cards have four words.
However, in the manuals I see that you can request up to 64 words. How can you do this? Is it possible for me to use one BTR or BTW instruction for the whole logical rack 0? Would I use a requested word count of 8 for the NO4I in the BTW instruction? If this is the case, then would I have to use two block transfer instructions because I'm crossing into rack 1?
Most of the examples I'm finding show you what to do if you have one analog input card or output card in your ASB rack. I really need an example showing two or more.
Thanks
I actually am going to be using a 1747-SN connected to a rack with a 1747-ASB and four analog input and output cards (NI4 in slot 1, NO4I in slots 2 and 3, and an NT4 in slot 10). The other slots will have IA16 and OA16 cards and will map discretely. I plan on using 1-slot addressing. If I start at Rack 0, Group 0 (and if I understand this correctly) then I'll be using slot 0 in Group 0 for the NI4, slot 0 in Group 1 for one NO4I, slot 0 in Group 2 for the other NO4I, and slot 0 in Rack 1, Group 1 for the NT4 (the other input and output cards fill the intermediate groups).
My question is this...do I have to have individual block transfer instructions for eack group? My first thought is "yes" because I have to specify rack, group, and slot in the BTR/BTW instructions. If this is the case, then I'm assuming my "requested word count" for each BTR/BTW instruction would be 4, since these analog cards have four words.
However, in the manuals I see that you can request up to 64 words. How can you do this? Is it possible for me to use one BTR or BTW instruction for the whole logical rack 0? Would I use a requested word count of 8 for the NO4I in the BTW instruction? If this is the case, then would I have to use two block transfer instructions because I'm crossing into rack 1?
Most of the examples I'm finding show you what to do if you have one analog input card or output card in your ASB rack. I really need an example showing two or more.
Thanks