1. CPU Extended Control, EC-mode bit must be turned on in the PSW to enable DAT
2. Load the segment table address of the program in STOR
3. LPSW to load the program PSW with the translation bit (5) on
4. DAT verify the segment number is within the length of segment table (part of STOR). If out of range, program is terminated with 0C4.
5. DAT check the segment entry invalid bit. If it is 1. DAT returns segment translation error to OS
6. DAT checked the PTE and if GETMAIN bit is off, DAT returns program check error 0C4
7. If PTE invalid bit is off, the page is in main memory
8. If PTE invalid bit is on, a page fault is triggered and OS will bring the page in. During this time, the program lose control of CPU.
24 bit and 31 bit address will be padded with zeros on the left to 64 bit before DAT translate it or prefixing translate it
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