* \057 C
$CSI    RES     0
S9300   EQU     0
X0      EQU     S9300
X2      EQU     2-S9300
CH      EQU     0
U       EQU     1
$INPUT  RES	    0
CARD    PZE	    0
CKSK    CRT     CH,U
        BRU     CKSK
        RCD     CH,U,4
        LDX     =00200000-20,X0
CWIM    WIM     CBFE,X2             ((CBFE,2):=(W)
        BRTW
        BRX     CWIM,X0
        BETW
        BRU     CSKSE
        BRR     CARD                EXIT**
CSKSE   HLT                         HALT ON MIS-READ
        BRU     CKSK
*
*
$ENDSI  PZE     0
        BRR     ENDSI
        END