PEP Modular Computers Modular Computers RS485 User Manual page 76

SMART I/O User's Manual
O_PRELOAD
<RetVar> := OPERATE(<iovar>, O_PRELOAD, <prevar>);
O_START_CNTDWN
<RetVar> := OPERATE(<iovar>,O_START_CNTDWN,<prevar>);
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: With this call the counter preload register can be
set. The syntax is as follows :
where the <iovar> is typically t_in and
<prevar> is the value for the preload register
which lies between 1 and 0xFFFFFF.
: This function starts the counter counting-down.
When the counter reaches zero, it rolls over to the
maximum value of 0xFFFFFF on the following
clock pulse and starts afresh. The syntax is as
follows :
where the <iovar> is a variable attached to the
Timer I/O (typically t_in) and <prevar> may be
one of OA_PITCLOCK for selection of the
6 MHz/32 clock input or OA_TIN for selection of
t_in inputs.
©1996 PEP Modular Computers GmbH
Chapter 2 SMART-BASE
March 12, 1996