AH500 Programming Manual 8. When chkHCR is ON, the practical device represented by HC50 is VarHCR1. Since the legal range of deices is from HC0 to HC63, and HC50+10-1=HC59, which does not exceed the range, HCR_ChkBit is ON. Additional remark: 1. If the value (the practical device address) in S exceeds the device range, the instruction CHKADR is not executed, SM is ON, and the error code in SR0 is 16#2003. 2. If the value in the operand n is not within the range between 1 and 1024, the instruction CHKADR is not executed, SM is ON, and the error code in SR0 is 16#200B. 6-35