CMH117@PSUVM.BITNET (Charles Hannum) (12/01/89)
I know this really isn't revelant to the group, but you're all probably
using IBM 'frames anyway, and there is no group pertaining to VM/CMS.
So, here goes:
Exactly what *are* Channel-To-Channel Adapters (CTCAs), and what do
they (and CP COUPLE) do?
Any info (other than the useless IBM help files) would be appreciated.
--
- Charles Martin Hannum II "Klein bottle for sale ... inquire within."
(That's Charles to you!) "To life immortal!"
cmh117@psuvm.{bitnet,psu.edu} "No noozzzz izzz netzzzsnoozzzzz..."
c9h@psuecl.{bitnet,psu.edu} "Mem'ry, all alone in the moonlight ..."klute@trillian (12/01/89)
Path: trillian !klute In article <89334.194519CMH117@PSUVM.BITNET> CMH117@PSUVM.BITNET (Charles Hannum) writes: >I know this really isn't revelant to the group, but you're all probably >using IBM 'frames anyway, and there is no group pertaining to VM/CMS. No, we don't - at least not me. I am using an Siemens 7500 under the BS2000 operating system. It has the same machine architecture and machine instructions as an IBM mainframe but of course the operation system is quite different. Most of the time this group is quite boring to me because so many IBM specific topics are discussed. Any more out there interested in Siemens mainframes and BS2000? Dipl.-Inform. Rainer Klute klute@heike.irb.informatik.uni-dortmund.de Univ. Dortmund, IRB klute@unido.uucp, klute@unido.bitnet Postfach 500500 |)|/ ...uunet!mcvax!unido!klute D-4600 Dortmund 50 |\|\ Tel.: +49 231 755-4663
klute%trillian@laura.UUCP (12/01/89)
Path: trillian !klute In article <89334.194519CMH117@PSUVM.BITNET> CMH117@PSUVM.BITNET (Charles Hannum) writes: >I know this really isn't revelant to the group, but you're all probably >using IBM 'frames anyway, and there is no group pertaining to VM/CMS. No, we don't - at least not me. I am using an Siemens 7500 under the BS2000 operating system. It has the same machine architecture and machine instructions as an IBM mainframe but of course the operation system is quite different. Most of the time this group is quite boring to me because so many IBM specific topics are discussed. Any more out there interested in Siemens mainframes and BS2000? Dipl.-Inform. Rainer Klute klute@heike.irb.informatik.uni-dortmund.de Univ. Dortmund, IRB klute@unido.uucp, klute@unido.bitnet Postfach 500500 |)|/ ...uunet!mcvax!unido!klute D-4600 Dortmund 50 |\|\ Tel.: +49 231 755-4663
jcmorris@mbunix.mitre.org (Morris) (12/02/89)
In a recent article CMH117@PSUVM.BITNET (Charles Hannum) writes: > > Exactly what *are* Channel-To-Channel Adapters (CTCAs), and what do > they (and CP COUPLE) do? > The CTCA is usually used to provide a dedicated, high-speed (typically 3 megabyte/sec) data path between mainframes. The CTCA itself (which can be either a feature on the processor or a stand-alone device) appears to be an I/O device to each processor attached to it. At the hardware level, that's all it is...in effect, a very expensive (but very fast) null modem cable. In VM you can create virtual CTCA ports with the CP DEFINE CTCA [as] cuu command; you then use the CP COUPLE command to say what is attached to the other end of the virtual cable by giving the userid and virtual address of the distant end. For example, if A and B want to communicate over a virtual CTCA, then: A issues the command: CP DEFINE CTCA AS 333 B issues the commands: CP DEFINE CTCA AS 444 CP COUPLE 444 TO A 333 and now A and B have a CTCA between them. What you do with the link is up to your programming system. It could be used for data transfer, for supervisory data transfer (e.g., passing ENQ/DEQ commands between processors which share DASD), or whatever you want. Hope this helps... Joe Morris
jcmorris@MBUNIX.MITRE.ORG (Morris) (12/02/89)
In a recent article CMH117@PSUVM.BITNET (Charles Hannum) writes: > > Exactly what *are* Channel-To-Channel Adapters (CTCAs), and what do > they (and CP COUPLE) do? > The CTCA is usually used to provide a dedicated, high-speed (typically 3 megabyte/sec) data path between mainframes. The CTCA itself (which can be either a feature on the processor or a stand-alone device) appears to be an I/O device to each processor attached to it. At the hardware level, that's all it is...in effect, a very expensive (but very fast) null modem cable. In VM you can create virtual CTCA ports with the CP DEFINE CTCA [as] cuu command; you then use the CP COUPLE command to say what is attached to the other end of the virtual cable by giving the userid and virtual address of the distant end. For example, if A and B want to communicate over a virtual CTCA, then: A issues the command: CP DEFINE CTCA AS 333 B issues the commands: CP DEFINE CTCA AS 444 CP COUPLE 444 TO A 333 and now A and B have a CTCA between them. What you do with the link is up to your programming system. It could be used for data transfer, for supervisory data transfer (e.g., passing ENQ/DEQ commands between processors which share DASD), or whatever you want. Hope this helps... Joe Morris
mercer@ncrcce.StPaul.NCR.COM (Dan Mercer) (12/03/89)
In article <89334.194519CMH117@PSUVM.BITNET> CMH117@PSUVM.BITNET (Charles Hannum) writes:
:I know this really isn't revelant to the group, but you're all probably
:using IBM 'frames anyway, and there is no group pertaining to VM/CMS.
:So, here goes:
:
: Exactly what *are* Channel-To-Channel Adapters (CTCAs), and what do
: they (and CP COUPLE) do?
:
:Any info (other than the useless IBM help files) would be appreciated.
:
:--
:- Charles Martin Hannum II "Klein bottle for sale ... inquire within."
: (That's Charles to you!) "To life immortal!"
: cmh117@psuvm.{bitnet,psu.edu} "No noozzzz izzz netzzzsnoozzzzz..."
: c9h@psuecl.{bitnet,psu.edu} "Mem'ry, all alone in the moonlight ..."
Normally, physical lines are attached to Channels. An RSCS connection
or a VM PassThru line might connect to another machine at 9.6 Kb.
If the two machines are located close enough (usually <= 100 ft) a
CTCA can be used to connect the two machines, allowing for a
much higher transfer rate. There's also a Virtual CTCA. A VCTCA,
which is software, allows you to connect two "machines" residing
in the same physical box (i.e. VM yo MVS).
--
Dan Mercer
Reply-To: mercer@ncrcce.StPaul.NCR.COM (Dan Mercer)mercer@UUNET.UU.NET (Dan Mercer) (12/03/89)
In article <89334.194519CMH117@PSUVM.BITNET> CMH117@PSUVM.BITNET (Charles Hannum) writes: :I know this really isn't revelant to the group, but you're all probably :using IBM 'frames anyway, and there is no group pertaining to VM/CMS. :So, here goes: : : Exactly what *are* Channel-To-Channel Adapters (CTCAs), and what do : they (and CP COUPLE) do? : :Any info (other than the useless IBM help files) would be appreciated. : :-- :- Charles Martin Hannum II "Klein bottle for sale ... inquire within." : (That's Charles to you!) "To life immortal!" : cmh117@psuvm.{bitnet,psu.edu} "No noozzzz izzz netzzzsnoozzzzz..." : c9h@psuecl.{bitnet,psu.edu} "Mem'ry, all alone in the moonlight ..." Normally, physical lines are attached to Channels. An RSCS connection or a VM PassThru line might connect to another machine at 9.6 Kb. If the two machines are located close enough (usually <= 100 ft) a CTCA can be used to connect the two machines, allowing for a much higher transfer rate. There's also a Virtual CTCA. A VCTCA, which is software, allows you to connect two "machines" residing in the same physical box (i.e. VM yo MVS). -- Dan Mercer Reply-To: mercer@ncrcce.StPaul.NCR.COM (Dan Mercer)
CMH117@PSUVM.BITNET (Charles Hannum) (12/04/89)
Okay, okay, everyone! I've got the picture! My reader is overflowing!
PLEASE stop sending me mail on this!
Anyway, thanks for the info, everyone who responded.
--
- Charles Martin Hannum II "Klein bottle for sale ... inquire within."
(That's Charles to you!) "To life immortal!"
cmh117@psuvm.{bitnet,psu.edu} "No noozzzz izzz netzzzsnoozzzzz..."
c9h@psuecl.{bitnet,psu.edu} "Mem'ry, all alone in the moonlight ..."drake@ibmarc.uucp (Sam Drake) (12/09/89)
In article <89334.194519CMH117@PSUVM.BITNET> CMH117@PSUVM.BITNET (Charles Hannum) writes: > Exactly what *are* Channel-To-Channel Adapters (CTCAs), and what do > they (and CP COUPLE) do? CTCAs are devices that allow two S/370 mainframes to communicate at channel speeds. So while most 370 I/O involves the CPU talking to a disk drive or some peripheral, CTCA I/O is CPU-to-CPU. One side can read a CTCA and will get an interrupt when the other side writes it...and vice versa. The IBM 3088 is a stand-alone product that provides channel to channel adapters; up to 8 mainframes can be hooked to the 3088 and they can all communicate using CTC protocols at full channel speed (4.5MByte/sec, I think). Under VM, virtual machines can manipulate real CTCs (if they are ATTACHed or DEDICATEd to the virtual machine), and can also use virtual CTCs. Virtual CTCs don't hook to any real hardware anywhere, but rather can be used to communicate between two virtual machines. Each virtual machine DEFINEs a CTC; the COUPLE command is used by one virtual machine or the other to connect them together. Sam Drake / IBM Almaden Research Center
drake@UUNET.UU.NET (Sam Drake) (12/09/89)
In article <89334.194519CMH117@PSUVM.BITNET> CMH117@PSUVM.BITNET (Charles Hannum) writes: > Exactly what *are* Channel-To-Channel Adapters (CTCAs), and what do > they (and CP COUPLE) do? CTCAs are devices that allow two S/370 mainframes to communicate at channel speeds. So while most 370 I/O involves the CPU talking to a disk drive or some peripheral, CTCA I/O is CPU-to-CPU. One side can read a CTCA and will get an interrupt when the other side writes it...and vice versa. The IBM 3088 is a stand-alone product that provides channel to channel adapters; up to 8 mainframes can be hooked to the 3088 and they can all communicate using CTC protocols at full channel speed (4.5MByte/sec, I think). Under VM, virtual machines can manipulate real CTCs (if they are ATTACHed or DEDICATEd to the virtual machine), and can also use virtual CTCs. Virtual CTCs don't hook to any real hardware anywhere, but rather can be used to communicate between two virtual machines. Each virtual machine DEFINEs a CTC; the COUPLE command is used by one virtual machine or the other to connect them together. Sam Drake / IBM Almaden Research Center
PERSHNG@YKTVMH3.BITNET ("John A. Pershing Jr.") (01/12/90)
If you look at the NUCON mapping macro, you will notice that it provides
symbolic names for all of the low-storage locations. It is considered
preferable to use these symbolic names, rather than absolute addresses.
Just remember to provide an appropriate USING pseudo-op in your assembler
routine:
USING NUCON,0
Note, also, that CMS normally protects its data areas (which includes
Page Zero) with a storage key of x'F' and runs user programs under a PSW
key of x'E', so you will have a bit of trouble storing into these low-
storage locations (e.g., the CAW). You can use the DMSKEY macro to ask
CMS to set the PSW key to x'0', or (a bit "safer") use the DMSEXS macro
to execute a single instruction (e.g., a store into the CAW) under a PSW
key of x'0'.
John Pershing
IBM Research, Yorktown Heights