The text read off it
[05.06.03]
B. Loader
The successful loading of an object program will be accompanied by the following messages:
- A list of the object-time tape assignments with appropriate mounting instructions will be printed on-line.
- Just prior to control being turned over to the object program, a message will be printed and a computer stop will occur to insure that the necessary object-time tapes have been mounted. The operator should press the Start button when the mounting instructions have been carried out. (This procedure will undoubtedly change, but the field test version of the CT Processor will operate in this manner).
- A message should now print saying that control has been turned over to the object program.
In addition, I/O messages concerning tape switching and redundancy may be printed on the on-line printer.
The CT Loader references the units SYSLB1, SYSIN's, SYSOU's, SYSUT1, SYSUT2, and SYSUT3. SYSUT1 is needed only if the run is of the type 'Compile and Load', in which case SYSUT1 contains the job to be loaded. Tape movement during loading consists of the following:
| Loading Phase | Unit Function | Action | Action Description |
|---|---|---|---|
| First pass over text | SYSIN1 or SYSUT1 | Read | Source of input |
| SYSLB1 | Read | Source of Loader and object subroutines | |
| SYSUT2 | Write | Write text needing further processing | |
| SYSUT3 | Write | Write text needing no further processing | |
| SYSUT2 | Rewind | ||
| Second pass over text which referred to locations undefinable during first pass | SYSUT2 | Read | Read text needing further processing |
| SYSUT3 | Write | Write text defined in this pass | |
| SYSUT2 | Rewind | ||
| SYSUT3 | Rewind | ||
| Read in object instructions and transfer to program | SYSUT3 | Read | Read final program into core |
| SYSUT3 | Rewind |
Loading-phase tape usage table (page 106).