Page of GC20-1801-10 As Updated March 3, 1980 by TNL GN25-0776 RCTLUNIT Kacro The RCHBLOK contains an index to each of thirty-two possible RCUBLOKS. When the ALTCH operand is specified on the RCTLUNIT macro, both the
primary and alternate RCHBLOKS contain an index to the same RCUBLOK. The following message is issued when an RCTLUNIT macro is defined
specifying the ATLCH operand and an RCTLUNIT macro is also defined which
creates an RCUBLOK for the alternate channel address.
CHANNEL TABLE FOR RCUxxx IN USE BY RCUyyy For Example: RDEVICE ADDRESS=250 RDEVICE ADDRESS=350 RCTLUNIT ADDRESS=250,ALTCH=(3) RCTLUNlf ADDRE55=350 RCHANNEL ADDRESS=2 RCHANNEL ADDRESS=3 The ALTCH specification indicates that the RCHBLOK for channel three
should index to the 250 RCUBLOK. The RCTLUNIT macro for 350 causes a
conflict since the RCHBLOK cannot index to both the 250 and 350 RCUBLOKS. In the above configuration, the user must remove the RCTLUNIT macro and RDEVICE macro for 350. 154 IBK VM/370 Planning and System Generation Guide

April 1, 1981
RCHANNEL Macro RCHANNEL Macro Use the RCHANNEL macro to generate a real channel block (RCHBLOK). An
RCHANNEL macro instruction must be coded to define each real channel in
the I/O configuration.
The RCHANNEL macro instructions describing the channels for your
installation may be in any order, but they must be contiguous and follow
all of the RCTLUNIT macro instructions in the module DMKRIO. The first
RCHANNEL macro instruction also generates the label DMKRIOCH, which
indicates the start of the real channel blocks to CP. No name is specified for the RCHANNEL macro instruction; if a name is
specified, it is ignored. The RCHANNEL macro generates a name by appending the channel address to the characters RCHAN. For example, if
the channel address is 2, the name RCHAN2 is generated.
The format of the RCHANNEL macro is: I Name Operation Operands 1---- 1 I I I RCHANNEL AD tRESS= address ,CHTYPE={SELECTOR ) MULTI PLEXOR BLKMPXR J ADDRESS=address is the real address of the channel. It is a hexadecimal number from
o to F. CHTYPE={SELECTOR } MULTIPLEXOR BLKMPXR is the type of channel. SELECTOR indicates a selector channel. MULTIPLEXOR indicates a byte-multiplexer channel. BLKMPXR indicates a block multiplexer channel.
The following examples illustrate the use of the RCHANNEL macro
instruction to describe a multiplexer channel whose address is 0, a
selector channel whose address is 1, and a block multiplexer channel
whose address is 2.
RCHANNEL
RCHANNEL
RCHANNEl ADDRESS=O,CHTYPE=MULTIPLEXOR ADDRESS=1,CHTYPE=SELECTOR If any errors are detected, the real channel block is not generated.
This results in undefined symbols in the real control unit blocks for
this channel. Part 2. Defining Your VM/370 System 155