IBM System/370 145 Reference Summary page 62

CONTROL COMMANDS
Command
Mnemonic Hex
Compact Data Mode MODE=DATA 00/10
File Pause FILE PAUSE 00/11
Byte Check NOP 02/12
Diagnostic Mode 3 MODE=D3 03/13
M-Register Duplicate Check STP=M-DUP 04/14
S-Register Duplicate Check STP=S-DUP 05/15
II
ALU Check STP=ALU
06/16
C-Register Parity Check STP=C-PTY
07/17
Advance Byte Counter by +17
BYTCTR + 17 08/18
Diagnostic Stop DIAG=STOP 09/19
Force Parity CFDA/CMMD Regs CMD&ADR-P OA/1A
Error Check STP=NO-CK OB/1B
Diagnostic Mode 1 MODE=D1 OC/1C
Diagnostic Mode 2 MODE=D2 OD/1D
Diagnostic Mode Normal MODE=NORM OE/1E
Reset CF Checks RST-CHKS
OF/1F
File End FILE-END 40/50
File Wait FILEWAIT 41/51
S~ctor
End SEND 42/52
Conditional Sector End SEND-IFMM
44/54
Set CFDA No Sector End SET-CFDA 4A/5A
Extra Bit Check EXTRA-BIT 4C/5C
Shift-Register Parity SHIFT-PTY
4D/5D
Block Stop Bit NO-STPBIT
4E/5E
Odd-Even Byte Check INVRTBIT3 4F/5F
OPERATION COMMANDS
Command Mnemonic Hex
CFDR to C-Register C=R 20
CFDR to C-Register and Execute C-R,X 30
Disk to C-Register C=LR 60
Disk to C-Register and Execute C-LR,X
70
Disk
to
C-Register and Execute C-LR,mmm 78
C-Register in Compare Mode to
7F
Execute C-Register with Direct X,LS 80
Local Store Addressing, CF DR
Data
Execute C-Register with Direct LR,X,LS
co
Local Store Addressing, Disk
Data
CONSOLE-FILE DISK ADDRESS (CFDA) BYTE
• First byte read in any sector
• Contains sector address (track and sector)
• Address range is 00 to FF (256 sectors)
COMPARE MODE
When an operation's command is decoded, bit 4
is checked. When bit 4 is 1, the command is per-
formed in compare mode. Compare mode is
applicable only to commands 0010, 0011, 0110,
0111 (20, 30, 60, 70).
Execution of the word in the C-register results
in setting up the next control word address in
the M (N) register even though that address is
not used to access the next control word.
M3 bits 3, 4, and 5 are frequently set according
to the result of branch testing. Bits 5, 6, and 7
in a command byte specifying compare mode
are compared to M3 bits 3, 4, and 5 so that set·
ting of M3 bits 3-5 can be checked. To use
comparison checking, the diagnostic program-
mer must set up the command byte bits 5-7
so that the next control word address is checked.
Bits 5-7 of the command byte correspond to
M3 bits 3-5 as fol lows.
Command Byte Bits
M3 Bits
567 345
000 000
001
001
010 010
111 111
If a mismatch occurs in compare mode checking,
the diagnostic stop latch sets. The file and CPU
operations stop, and the system diagnostic stop
check indicator turns on. If the command byte
bits 5-7 match M3 bits 3-5, the console file
operation continues.
3.2