Field | Subfield | Description |
---|---|---|
00 | Interface Type 0 = MLI interface 1 = IPI Interface 2-F = Reserved |
|
01 | IOP Variant Extension (Presently zero) | |
02-03 | IOP Variant. Setup by software, used unmodified by the IOS | |
02 | 3 = Inhibit Data Transfer to memory 2 = Backwards Read 1 = ASCII Translation 0 = Real Time |
|
03 | 3 = Reserved 2 = Reserved 1 = Bypass I/O complete Queue (Software polls IOP R/D for completion) 0 = Conditional Cancel Flag |
|
04-13 | Buffer Begin Address. Absolute Value Used and modified by IOS Content not guaranteed at I/O complete. May be Set by CIO |
|
14-23 | Buffer Size Number of digits to transfer by IOS Initial Value Only. |
|
24-27 | IOP Accumulated R/D. Compatibility Notes A.64 | |
28-31 | Remaining Data Length & R/D Field Offset. Offset relative to current IOCB begin address. |
|
32-33 | Reserved | |
34-39 | Buffer MAST Number Memory Area nailed by CIO Not used by IOS. Used by IOC to unnail Memory Area |
|
40-43 | Special R/D Used by software only Valid only if Bypass I/O complete queue bit set in IOP Variant Value “8000” = I/O completed. Value “0000” = I/O not completed. |
|
44-45 | Unit Number Compatibility Notes A.64 | |
46-49 | Channel Number Where the DLP command is sent Set by Software See Compatibility Notes A.24 |
|
50-NN | DLP Command or I/O Op Code MLI: NN=69 IPI: To Be Specified Built by software Set unmodified by IOS to DLP except for Unconditional Cancel |
|
MM-PP | Remaining Data Length and Result Descriptors MLI: MM=70, PP=107 IPI: To be specified Used and modified by IOS Content guaranteed at I/O complete |
Field | Subfield | Description |
---|---|---|
50-69 | DLP Command - MLI Interface | |
50 | DLP Op Code C = Unconditional Cancel 8 = Read 4 = Write 2 = Test 1 = Echo |
|
51-53 | DLP Variants | |
54-61 | Peripheral Device Information Formerly known as the C-Address |
|
62-69 | Peripheral Device Information Extension Number of bytes (Buffer Size divided by two) in binary to be transfered to the device |
Field | Subfield | Description |
---|---|---|
70-107 | Remaining Data Length and Result Descriptors - MLI Interface Only current I/O operation relevent field updated by hardware |
|
70-79 | Remaining Data Length Number of digits not transferred Used and updated by IOS Content guaranteed at I/O Complete May be set by CIO |
|
80-83 | IOP R/D Compatibility Notes A.64 | |
84-91 | DTM R/D Compatibility Notes A.64 | |
92-107 | DLP R/D |
The remainder of the IOCB is reserved for software use.