Page | 13 When the assembler gets to the BNE instruction (at which point the LC stands at 67), it searches the symbol table for AB , and finds it. However,
AB has a type of U , which means that it is a future symbol and thus its value field (=36) is not a value but a pointer It should be noted that, at this point, a type of U does not necessarily mean an underlined symbol. While the assembler
is performing its single pass, any underlined symbols must be considered future symbols. Only at the end of the pass can the assembler identify underlined symbols (see below).The assembler handles the BNE instruction by i)
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