Measurement Computing ADAC/5500 Series Installation - Manual (Page 13)

Signal Definitions for P3, P5, and GB17’s DB37 Connector
The following descriptions apply to each of the signals that are available at the 40-pin auxiliary DIO headers,
designated as P3 and P5. The headers are located on the back of boards: ADAC/5501MF, ADAC/5502MF,
ADAC/5503HR, and ADAC/5504HR. In addition, the signals apply to the corresponding pins on GA17’s DB37
connector as indicated in the table on the preceding page.
GA17’s orb (following figure) mounts at the back of the host PC.
The DB37-end of a CA-G17-ADAC Cable, which includes an Orb for PC Mounting
D0... D15 These signals are the sixteen 5 V CMOS/LSTTL level digital input/output lines of DIO2 on
connector P3, and the D103 connector on P5.
On G17’s DB37 connector, D0 through D15 correspond to pins 21 through 36, with DB0
assigned to pin 21, DB1 assigned to pin 22, DB2 assigned to pin 23, etc.
DGND This signal is the +5 V power return line. It may also be used as a reference ground for TTL
signals. On G17’s DB37 connector, the DGND lines connect to pins 1 through 19, inclusive.
+5 V This signal is +5 V power voltage signal that is sourced directly from the PC bus. The +5 V lines
are fused at 3 amps. See WARNING. On G17’s DB37 connector, the +5 V power signal
corresponds to pin 20.
WARNING
Possible electric shock. Take great care when using the +5 V power as the voltage signal is
sourced directly from the PC Bus. The +5 V lines are fused at 3 Amps.
STROBE The Strobe2 signal is provided on the DIO2 37-pin interface and the Strobe3 signal is provided on
the DIO3 interface. When either port is configured as an input port, the associated Strobe signal is
disabled and placed in a High Impedance state (Z off). When DIO port is configured as an output
port, the associated strobe signal will be pulsed low for 1 microsecond following each data output
event that occurs.
On system power-up the DIO Strobe signals are disabled and placed in a High Impedance state
(Z off). 3.3 V CMOS signal.
In regard to the G17 DB37 connector, pin-37 is used for the strobe signal.
1107-0940, rev 2.0 908096 ADAC/5500 Series Installation Guide 13