The SEC-PC (full name: Shaft Encoder Counter Interface) is a board that plugs into an 8-bit slot in your PC. It allows you to interface to up to three linear or shaft encoders.
It accepts six encoder inputs (three Quadrature-encoded pairs) and maintains 24-bit counters for each axis. (A fourth axis option is available.)
The front end logic is synchronous to the system clock and pretty much doesn't miss counts. Rate error logic detects input transitions that occur too swiftly, and incidentally also detects noise pulses on the inputs.
To read the counters, the user first copies them simultaneously to latches, an operation that occurs synchronously to the counting clock. The user can then read the latches in a hazard-free manner.
There is a debounced and latched input for an operator switch, four LED drivers, as well as general-purpose input and output signals. There is a socket for a security ROM or RAM.
For more information, contact Fischer Computer Systems at 1707-965-2414 or at www.secpc.com.