Technical information

OPTO DIO Reference OPTO OUT48
Note when using the INVERTING ULN2804 SINK DRIVERS
the Watch Dog signal is also inverted by these drivers, thus the
RESHI/LO and GOODHI/LO legends are the inverted.
Figure 4-9. Watchdog Output Select.________________________________
FACTORY SET___________
.. PORT A1 Bit 0 Output. Via Pin 34 of 50D, pin 1 of 50IDC.
. . WatchDog Out Signal Output. Via Pin 34 of 50D, pin1 of 50IDC.
.... WatchDog Out Signal Output. Attach flylead for use inside PC
Pin 3 = Watch dog signal NOT OPTICALLY ISOLATED
34 Pin 4 = PC ground NOT OPTICALLY ISOLATED
Opto DIO48 Memory Map.________________________
The Opto OUT48 has 48 dedicated output lines arranged as
6 eight bit read/write registers and one read/write watchdog
enable/strobe register and one unused register. So the OUT48
card occupies 8 consecutive i/o addresses. See Figure 4-10. The
output ports are output only, however the output registers are
read/write, writing to them sets the level of the output lines,
reading them provides a read back of the previously written
value. On power up, all the output lines are reset to zero, low, ie
the output drivers are off.
Writing data to the Port A#1, B#1, C#1, A#2, B#2 or C#2
registers sets the external output line high or low. Reading from
the ports returns the previously set value. Writes to the watchdog
register gate the signal selected by the BUS jumper onto IRQ
line or RESET line of the PC. Reading the watchdog register
refreshes the timer postponing timeout for another 50millisecond.
Page 46 Chapter 4