Z-World eDisplay OP7200, Руководство пользователя

Страница: 21 / 152

User’s Manual 15
3.2 Indicators
3.2.1 LEDs
The OP7200 has two LEDs, Power Good and Microprocessor Bad .
The green Power Good LED at DS2 indicates when power is applied to the OP7200 and
that Vcc is within the proper operating range of 4.5 to 5.5 V. The LED turns off when the
OP7200 is being reset.
The red Microprocessor Bad LED at DS1 indicates the status of the OP7200. Following
reset, DS1 will be ON and will remain ON until turned OFF by Dynamic C. Once the
microprocessor comes out of reset and finishes all its internal checks and initializes the
system, it should turn DS1 OFF.
The operation of DS1 may be redefined in any manner desired with the caveat that DS1
comes ON after reset. The
USR label on the dust cover refers to the LED at DS1 and
reflects its secondary purpose as a user-defined indicator.
3.2.2 Buzzer
An audible buzzer is turned on and off through the use of a programmed I/O bit defined in
software.