On this page is described an interface to pick out the data from a digital
caliper gauge.
Everyone knows the cheap caliper gauges, which are offered with a serial
interface in any internet stores. The caliper has a serial data output and
so, it spurred the hope of many to be able to attach this good piece to
the PC. Here the customer errs.
The problem concerns the serial interface as implemented. It is not the
long known asynchronous serial interface that our computer normally uses,
but instead, it involves a synchronous serial interface. At the end of the
year 2000 I started together with
Lee Studley
to decode this interface. In
addition, it spawned some discussions in October 2000 in the discussion
group CAD_CAM_EDM_DRO
. Here
you can find a ascertained protocol of the caliper gauge, which served
then as basis for programming. Those who continue to pursue this thread,
receives for their troubles still more details. On this page is described
the building of an interface for the selection of the data from a digital
caliper gauge.
The data can be picked out serially at the PC and/or be represented on a
LCD display.
The interface functions with the caliper gauges, in whose operating
instructions the following minutes are described:
Working way ofinterface: Synchronus serial
DATA: Binary code, 24 bits, each date
wants sends twice
Clock pulse of CP: 90 kHz
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