J Guy wrote:-----------------------
"You must still have Z-80, which does have that flag, on your mind."
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true

too bad zilog never made a good i/o focused microcontroller. it was a great microprocessor for applications requiring external memory. the 8051 has a safe niche.

J Guy wrote:-----------------------
"The JZ and JNZ instructions in 8051 depend on the ACC contents alone, so if your intention is to keep moving until the table contains a 0, it's missing an increment."
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the JZ and JNZ test the accumulator after the MOVC A,@A+DPTR, so its testing whether the last character read into the accumulator from the table was a zero, or not.

the INC instruction only advanced the table index or offset pointer but wasn't used in the loop termination code.

i recently worked on another micro that required something like an OR A,A to set the flag before a JZ instruction.

duh