Teledyne T200, Operation Manual, Page: 311 / 425

Teledyne API
– T200 NO/NO
2
/NO
X
Analyzer Operation Manual Principles of Operation
309
OPTICAL TEST (OTEST) CONTROL: When the CPU sets this control signal to
high ( ON ) the optical test feature is initiated (see Section 8.3).

The
OTEST
can be initiated by following the procedure in 12.7.12.1, or by setting
the SIGNAL I/O Function
OPTIC_TEST
to
ON
.
PMT PREAMPLIFIER RANGE CONTROL: The CPU uses this control switch the
instrument between its LOW and HIGH physical ranges (see Section 5.4.1).

The instrument can be forced into its HIGH physical range setting the SIGNAL I/O
function
PREAMP_RANGE_HI
to
ON
.
O
3
GEN STATUS: The CPU uses this control signal to turn the O
3
generator ON/OFF
by setting it to HIGH/LOW respectively. The CPU turns OFF the O
3
generator if there
is if there is no or low air flow to it as measured by the O
3
flow sensor or if the
instrument has been turned off for more than 30 minutes.

The O
3
generator can be manually turned
ON/OFF
by using the
OZONE
GENERATOR OVERIDE
feature (See Section 12.7.15.1) or by setting the SIGNAL
I/O function
O3GEN_STATUS
to
ON
or
OFF
.
Note Any I/O signals changed while in the signal I/O menu will remain in effect ONLY
until signal I/O menu is exited.
The analyzer regains control of these signals upon exit and returns them to their
normal value/setting.
13.3.3.7. I
2
C DATA BUS
I
2
C is a two-way, clocked, bi-directional digital serial I/O bus that is used widely in
commercial and consumer electronic systems. A transceiver on the Motherboard
converts data and control signals from the PC-104 bus to I
2
C format. The data is then
fed to the relay board, optional analog input board and valve driver board circuitry.
13.3.3.8. POWER-UP CIRCUIT
This circuit monitors the +5V power supply during start-up and sets the analog outputs,
external digital I/O ports, and I
2
C circuitry to specific values until the CPU boots and the
instrument software can establish control.
06858E DCN7057