; RESET_TLM - Resets Telemetry output board to 
;               i) halt current downlink or
;              ii) Recover from a board hang.
; 
; Restrictions:
;    1) Resets Prime Telemetry board only
;    2) Resets only page 8 or 9
;    3) A page must be initialised as list (8 byte EDAC) memory
;       with it's parameters in IP registers 136-143.
;
; Side Effects:
;    1) First 550 words of page 11 are clobbered.
;    2) IP Registers 552-560 are clobbered.
;
; Parameters:
;    1) $IPRL_TLM_PAGE - Page to be freed
;    2) $IPRL_TLM_STATUS - Status of the reset operation
;                              0 - Successful
;                              1 - Failed
;                           0xff - Reset not attempted
; 
; History:
;    Written by Dnyanesh Mathur, 17-Oct-95
;--------------------------------------------------------------------------
;
QSR_TLM_RESET::
;
    BRANCHIF R0081 &CKPAGE            ; HR OK => Continue Reset 
    SETREG   $IPRL_TLM_STATUS 0x00ff  ; Status Code = "RESET not attempted"
    RTNQUE                            ; HR NOK => Skip Reset
;
CKPAGE:
    BRANCHNR 0x4000  &DOHRDINIT       ; Page 8 busy => Do Reset
    BRANCHNR 0x4800  &DOHRDINIT       ; Page 9 Busy => Do Reset
    RTNQUE                            ; No Page Busy => Exit

DOHRDINIT:
    SETREG   $IPRL_TLM_STATUS  0      ; Assume success
;
    SETREGS  R552  6  1 0x0000  0x5800  0x00  0xCFFF 0xFF98
    HRDINIT  R552
    SETREGS  R558  2  0x00001L
    START1HR 0x33  0x5800  R558       ; D/L P11 to free P8
;
    COPYREG  R143  R552               ; Save Block Count
    SETREG   R143  16                 ; Set Block count to 16
    PURGELST R136                     ; While away 82 ms
    COPYREG  R552  R143               ; Restore Block Count
;
    BRANCHNR 0x4000 &ERREXT           ; P8 still busy => HR NOK
    BRANCHNR 0x4800 &ERREXT           ; P8 still busy => HR NOK
    RTNQUE
;
ERREXT:
    SETREG   $IPRL_TLM_STATUS   1
    RTNQUE