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TecMar --  Digital to Analogue Converter Board
The Tecmar S-100 D/A board was designed for applications requiring high speed accurate digital  to analog conversion including real  time applications.

DtoA Converter Board

 This board supported four independent high speed digital to analog converters  (DACs) with associated latches.    Each DAC operated com­pletely independent of the rest.    The DACs have a conversion time of 3 usec which enabledthem to operate at maximum computer speed.    A 12 bit latch drives the inputs of each DAC.    Another 4 bit latch for each DAC holdd the four new most significant bits waiting for the arrival  of the new least significant byte.    This allowed the DAC to hold its previous value until an entire new word was presented to it.    All the latches were set to zero by reset.    To modify the contents of a latch, and hence the output of a DAC, it was necessary to send two bytes to the device.    The input was a 12 bit two's complement number.    User selectable output ranges of 0 to +5V, 0 to +10V, ±2.5V,  ±5V, and ±10V were available.    The user had the option of adjusting offset and gain through external pots.    The board could be addressed as  I/O ports or memory mapped.    Only four lines of software were required to program these DACs!
The manual for this unique board can be obtained here.
Tecmar provided a Fortran library of sub-routines to use with this board. This manual can be obtained here.


Other TecMar  S-100 Boards
Digital to Analogue Converter     Analogue to Digital Converter         8086 CPU Board

This page was last modified on 10/25/2013