Panasonic FP Series Programming Manual page 991

System register instructions
Keyword setting
High-speed counter setting
n: 0 to 9, A, B with FP-X C14R, C30/60R
HSCn
n: 0 to 7 with FP-X C14T, C30/60T
n: 0, 1, 2, 3 with FPΣ
UP: Addition input setting
DOWN: Subtraction input setting
Precautions during programming
 If the corresponding HSC system register is set to Unused, an operation error
occurs. Set the system register to Incremental input or Decremental input in
advance.
 Executing this instruction does not rewrite the contents of the system ROM in the
control unit. As a result, turning the power supply off and then on again rewrites
the contents of the system registers specified by the software tool.
 We recommend to execute this instruction only once, e.g. in dependency of a
rising or falling edge of an execution condition.
 When UP or DOWN has been specified, the contents of the system registers
change in accordance with the specification, so a verification error may occur in
some cases when checking or compiling the program. When BOTH have been
specified, the contents of the system registers do not change. Separate the first
and the second keyword with a comma "," e.g. HSCB,UP; do not use spaces.
Otherwise an operation error will occur.
Error flags
No. IEC address
R9007 %MX0.900.7
R9008 %MX0.900.8
In this example the function has been programmed in ladder diagram (LD) and structured text (ST).
Example
POU header
Body
When bCountUp is set to TRUE, the function is carried out. The system register for the specified
channel is set to count up. When bCountDown is set to TRUE, the specified channel is set to
count down.
990
SYS1 HSC1,UP
Set If
permanently  any character other than a keyword is
specified
 no comma is between the first and second
for an instant
keyword
 the letters used to specify the keyword are
not capitalized
 the HSC system register is set to items other
than the addition input or subtraction input