ADC8.TXT         MVS Box 850 Merrimack,NH          3/20/94







   The ADC8 card is an 8 channel 8-bit Analog to Digital Converter with
   a 44khz sample rate.  Two of the channels have sharp cutoff filters
   for signal conditioning and noise reduction.  A 2.5 volt precision
   voltage reference is available for use with external circuitry. 
   Four TTL compatible output bits are provided for control of relays,
   indicators, and other devices.

   The ADC can be jumpered to run with 0-5v (unipolar) or -2.5 to +2.5v
   (bipolar) input.  Default is bipolar and is required for audio signals.
   Unipolar is usually used with data aquisition.  In both cases the lowest 
   value reads as 00h and the highest reads as FFh.

   Multiple channels are implemented with an analog switch type multiplexer.  
   Voltages from -5 to +5v can be input.  Three output bits select the 
   channel and a fourth bit functions as a track/hold signal.

   Dual 2-pole active filters improve record quality in stereo audio
   applications and allow longer cables in data aquisition applications. 
   These filters can be used independently from the ADC circuit.  This means
   they can be used to improve playback quality when switched to DAC outputs.
   A 4-pole filter can be implemented by placing them in tandem.

                                        Start Conversion (output) = 108h
   Signal Connector:                    Read Data (input)         = 109h
                                        Control Register (output) = 10Bh:
     1 Ground         2 NC                D0 = MPX Bit 0       D3 = TTL out A
     3 Ground         4 NC                D1 = MPX Bit 1       D4 = TTL out B
     5 Ground         6 NC                D2 = MPX Bit 2       D5 = TTL out C
     7 Ground         8 NC                D3 = trk(0) hold(1)  D7 = TTL out D
     9 Ground        10 Filter in A
    11 Filter in B   12 Filter out A    Base Address Jumpers:
    13 Filter out B  14 ADC in A         J1 J2 J3 J4   108h= 1-5 2-6 3-7 4-8* 
    15 ADC in B      16 ADC in C          o  o  o  o   110h= 1-6 2-5 3-7 4-8
    17 ADC in D      18 ADC in E          o  o  o  o   208h= 1-5 2-6 3-8 4-7
    19 ADC in F      20 ADC in G         J5 J6 J7 J8   210h= 1-6 2-5 3-8 4-7
    21 ADC in H      22 TTL out A        
    23 TTL out B     24 TTL out C       Voltage Range Jumpers:
    25 Ground        26 TTL out D              o J9     
    27 Ground        28 +5v              J10 o o J11   -2.5 to +2.5v = 10-11*
    29 Ground        30 +2.5v ref        J12 o o J13      0 to +5v   = 9-10
    31 Ground        32 -12v             J14 o o J15
    33 Ground        34 +12v             J16 o o J17           *default
                                         J18 o o J19

                         LIMITED WARRANTY 

MVS will repair free of charge product suffering from manufacturing defects
for a period of 5 years after shipping.  This will be done only if it has
been determined by MVS that the product has not been misused (improper
voltages, physical alteration, etc.).  Otherwise a minimum service charge
is required.  In either case it is necessary to contact MVS for a Returned
Merchandise Authorization (RMA) number before shipping the unit.