Citizen C500 Instruction Manual page 17

To delete all log data;
Button A
DIV
MAX
Button B
A SP
P
SEL CA
SET
SEL
STA
RES
STP
In case the depth indication flashes;
DIV
MAX
A SP
P
SEL CA
SEL SET
STA
RES
STP
LOG
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Depress button A and button B together
for 2 seconds or more and all log data will
be deleted.
This signifies that the log data is faulty.
In case ER (error) is shown;
DIV
MAX
A SP
P
SEL CA
SEL SET
STA
RES
STP
This signifies that the log data is faulty.
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