; MAG_DL_SETUP
;
; Routine to downlink stored magnetograms. This routine should be called
; by the VC2 campaign observation. The VC2 campaign observation generates
; a High-Resolution magnetogram.
;
; The downlink is started on the first frame of the VC2 OBS. At this time
; the velocity created by the Prime30 program is available in Page 5 and
; continuum in Page 6.
;
; The Call Number is incremented by the routine. It is reset by the CHEAD
; program.  
;
;
; Call Number        Page 1                   Page 2
;  (Minute)
;     1           Stored Mag 1              Velocity-CB
;                  (Velocity)
;
;     2           Stored Mag 2              Ic-CB
;                  (Velocity)
;
;     3           Stored Mag 3
;                 (No Mag Flag)
;
;     4           Stored Mag 4
;                 (No Mag Flag)
;
;     5           Stored Mag 5
;                 (No Mag Flag)
;
;     6            No Mag Flag 
;
;     7            No Mag Flag 
;
;     .                .
;
;......................
;
;  Calling Sequence:
;      CALLQUE    &MAG_DL_SET
;
;      The call updates the following registers:
;          $IPRL_MAG_DLPAGES      1st Page Number 
;
;          $IPRL_MAG_DLPAGES+1    2nd Page Number  
;
;          $IPRL_MAG_PGLEN1    LS word of length of Page 1
;          $IPRL_MAG_PGLEN1+1  MS word of length of page 1
;
;          $IPRL_MAG_PGLEN2    LS word of length of Page 2 (= 0 if no Page 2)
;          $IPRL_MAG_PGLEN2+1  MS word of length of Page 2 (= 0 if no page 2)
;
; Notes:
;  1. $IPRL_MAG_PAGE   = 0xA000 to indicate "No Mag Page" Condition
;  2. $IPRL_MAG_PAGE+1 = 0xFFFF if only 1 page is to be downlinked
;  3. $IPRL_MAG_DLC is incremented by 1 on each call
;  4. The LS Word for $IPRL_MAG_PAGE+1 is 0 for min1 and min2.
;
; HISTORY:
;	Written Nov-95 by D.Mathur
;	16-Nov-95 (MDM) - Modified how the $IPRL_MAG_PGLEN1 registers
;			  are set for stored magnetogram.  Copy the value
;			  from R71-72 instead of from $IPRL_MAG_DLPLEN
;			  (where it wasn't being set ever).
;        7-Feb-96 (DPM) - Changed downlink length for 800 minute circular
;                         buffers.
;	14-May-96 (MDM) - Changed source page for circular buffer from
;			  6001 to 7008 (LOI-V) and
;			  6005 to 7006 (LOI-C)
;......................
;
QSR_MAG_STORD_PG::
;
     ADDREGD   $IPRL_MAG_DLC        1
     BRANCHEQ $IPRL_MAG_DLC 1 &MIN_1
     BRANCHEQ $IPRL_MAG_DLC 2 &MIN_2
     GOTO &MIN_3
;
;......................
;
MIN_1:
     SETREG    $IPRL_MAG_DLPAGES+1     0x7008     ; $VEL_CB_PAGE
     SETREGS   $IPRL_MAG_PGLEN2     2       0x23F00L   ; $VEL_CB_LEN
     SETREG    $IPRL_MAG_P1DP       &DL_VEL
     CALLQUE   &SETP1
     RTNQUE
;
MIN_2:
     SETREG    $IPRL_MAG_DLPAGES+1     0x7006     ; $IC_CB_PAGE
     SETREGS   $IPRL_MAG_PGLEN2     2       0x23F00L   ; $LEN_IC_CB
     SETREG    $IPRL_MAG_P1DP       &DL_VEL
     CALLQUE   &SETP1
     RTNQUE
;
MIN_3:
     SETREG    $IPRL_MAG_P1DP       &DL_HRMAG
     CALLQUE   &SETP1
;
     SETREG    $IPRL_MAG_DLPAGES+1     0xFFFF
     SETREGS   $IPRL_MAG_PGLEN2     2       0L
     RTNQUE
;
;......................
;
SETP1:
;
     CALLQUE   &QSR_MAG_CKMAG
     BRANCHNE  $IPRL_MAG_DLPAGE     0xFFFF  &DL_STOR_MAG
;
     GOTOREG   $IPRL_MAG_P1DP
;
DL_STOR_MAG:
     COPYREG   $IPRL_MAG_DLPAGE     $IPRL_MAG_DLPAGES
;     COPYREG   $IPRL_MAG_DLPLEN     $IPRL_MAG_PGLEN1
;     COPYREG   $IPRL_MAG_DLPLEN+1   $IPRL_MAG_PGLEN1+1
     COPYREG   R71                  $IPRL_MAG_PGLEN1
     COPYREG   R72                  $IPRL_MAG_PGLEN1+1
     RTNQUE
;     
DL_VEL:
     SETREG    $IPRL_MAG_DLPAGES 0x2800     ; $VEL_PAGE
     COPYREG   R71                  $IPRL_MAG_PGLEN1
     COPYREG   R72                  $IPRL_MAG_PGLEN1+1
     RTNQUE
;
DL_HRMAG:
     SETREG    $IPRL_MAG_DLPAGES       0xA000
     SETREGS   $IPRL_MAG_PGLEN1     2       0L 
     RTNQUE
;......................
;
; Subroutine to downlink stored magnetograms
;
; The MAG30 routine sets a register for each page which contains a 
; completed magnetogram. This routine examines each register in turn
; and copies the first magnetogram found to the downlink page. 
;
;
QSR_MAG_CKMAG::
;
    SETREG    $IPRL_MAG_DLPAGE  0xFFFF
;
CKMAG:
    BRANCHIF  $IPRL_MAG_DONE1   &CKMAG2
    COPYREG   $IPRL_MAG_DONE1   $IPRL_MAG_DLPAGE      
    SETREG    $IPRL_MAG_DONE1   0
    RTNQUE    
;
CKMAG2:    
    BRANCHIF  $IPRL_MAG_DONE1+1 &CKMAG3
    COPYREG   $IPRL_MAG_DONE1+1 $IPRL_MAG_DLPAGE      
    SETREG    $IPRL_MAG_DONE1+1 0
    RTNQUE      
;
CKMAG3:    
    BRANCHIF  $IPRL_MAG_DONE1+2 &CKMAG4
    COPYREG   $IPRL_MAG_DONE1+2 $IPRL_MAG_DLPAGE      
    SETREG    $IPRL_MAG_DONE1+2 0
    RTNQUE      
;
CKMAG4:    
    BRANCHIF  $IPRL_MAG_DONE1+3 &CKMAG5
    COPYREG   $IPRL_MAG_DONE1+3 $IPRL_MAG_DLPAGE      
    SETREG    $IPRL_MAG_DONE1+3 0
    RTNQUE      
;
CKMAG5:    
    BRANCHIF  $IPRL_MAG_DONE1+4 &MAG_DL_END
    COPYREG   $IPRL_MAG_DONE1+4 $IPRL_MAG_DLPAGE      
    SETREG    $IPRL_MAG_DONE1+4 0
    RTNQUE      
;
MAG_DL_END:
    RTNQUE