st    r13,4(,r1)                                               00700000
         st    r1,8(,r13)                                               00710000
         lr    r13,r1                                                   00720000
         using workarea,r13                                             00730000
*                                                                       00740000
* Determine the message length                                          00750005
*                                                                       00760000
         slr   r1,r1              Number of bytes                       00770005
         l     r15,msgtxta        get starting address                  00780005
nulloop  ds    0h                                                       00790006
         cli   0(r15),x'00'       Is it zero?                           00800005
         je    nomore             Yes - quit                            00810005
         la    r1,1(,r1)          Bump count                            00820005