.title iovir .enabl lc .globl iovir .psect iovir ; ; IOVIR maps the 4k-word portion of virtual memory extending from octal ; 140000 to 157777 to the specific area in physical memory corresponding ; to the I/O page. This is necessary under TSX-Plus to accommodate ; programs that both use Fortran virtual arrays and directly address ; I/O page registers, such as those that call the LAPLOT subroutines. ; ; Fortran call: CALL IOVIR ; iovir: mov #mapphy,r0 ; point to EMT arg block to.. emt 375 ; ..map to physical memory rts pc ; return to Fortran ; mapphy: .byte 17,140 ; EMT arg block to map to physical memory .word 6 ; remap Page Address Register 6 ; (SETSIZ or the LINK /K:24. option ; must be used to avoid conflict with ; Fortran work space) .word 177600 ; 17760000/64. address to map into PAR 5 size: .word 200 ; size of region to be mapped - 4k words .word 1 ; access: 0=read only, 1=read/write .end