IBM 2790 Manual page 49

X 'C 7 '- Restore 2790 Input
• Function— Restores the read channels to the 2790 system,
which allows 2790 data input. A response message is
sent to System/360 unless the X'C7' was an invalid panel
request (see Note).
Note: After an ICPL, a 'set time' control request must
be executed before an X'C7' request will be accepted
as valid.
• Request Format
System/360 and Panel— Standard with no additional
data required.
• Response Format
See "General Responses" (following "X'C3'-Bypass
Segment").
X'C8'— Set Dual Communications Switch
X'C9'— Reset Dual Communications Switch
• Functions— These control requests are valid only on
2715 Model 2 with Dual Communication Interface
feature (see "Selective Features for 2715 Model 2").
The X'C ' control request switches the 2715 BSC adapter
8
from operation with the primary interface to operate
with the alternate interface.
The X'C9' control request switches back to operation
with the primary interface.
• Request Format
CE Panel— Standard format. •
• Response Format
CE panel request:
a. Positive— Standard format
b. Negative— Not used
c. Invalid— The following catalog numbers are displayed j
in the display register:
Cat. No. 0003— Requested configuration already
present.
Cat. No. 0004— Dual Communications Interface
feature not present.
Cat. No. 0007— Request made on 2715 Model
X'D 1 X'D2', and X'D 3'-U ser Table Load
• Function— These control requests allow the user to define
his 2790 system and operation to the 2715. The user
sends the user tables generated by a System/360 assembly
to the 2715, where they are loaded in core and written
on disk. These tables are used by the 2715 until the user
reconfigures his system with another 'user table load.'
The 2715 must be preconditioned with a 'stop 2790
input' control request or an ICPL. No other control
request may be interspersed within the 'user table load'
sequence. A 'restore 2790 input' must follow a 'user
table load' sequence if normal operation is to continue.
Note: A negative response results in altering the user
tables in the 2715 core. A successful 'user table load'
or an ICPL must be done prior to starting the 2790 input.
• Request Format
System/360 only-Standard format with:
X'D1'-Defines the start of 'user table load'; no data is
transmitted.
X'D2'— This control request byte is used as the transac­
tion control byte for sending the output of the
System/360 assembler. Each card from the object
deck is sent to the 2715 as a one-transaction message.
X'D3'-Defines the end of the user table. No data is
transmitted.
• Response Format
System/360 only:
a. Positive-Standard format (rt = X 'D1').
b. Negative— Standard format with one of the following
(in EBCDIC) for r
1— Name or sequence count error (col. 73-80 in card)
2— 2790 input not stopped
3— First card not ESD card
4— No END card
5— Table too large
— Invalid card type (columns 2-4)
6
7— X'D3' control request missing
— Wrong-length byte in user-table data
8
9— Wrong core-size assembly being loaded
A— 30-second timeout without receiving data
B— Other control message received before proper end
X 'D 4'-CP U Restart
.
1
• Function— Attempts to recover all deferred data that
was received after the restart number contained in the
request. This request must be preceded by 'reset read
deferred data mode'. The 'CPU restart' control request
is designed to operate in conjunction with a checkpoint/
(rx = X'D '):
2 1
Transmission Control Unit 49