Table of Contents
Advertisement
North Star HSIO-4
4.
If the port is functioning properly, a dot
displays on the screen for each of the 256
test characters sent to the port. At
successful conclusion, the following
displays:
There were 0 errors encountered
5.
If there is a malfunction, one of two error
messages will display:
A.
Input status not ready.__ Not receiving data]
Using an oscilloscope and referring to the
schematic, this test may be repeated to trace
the signal path from pin 19 (TXD) of the USART
(8251)— to the RS-232 driver (1448)— to the
test connector and back to the receiver
(1489)— to pin 3 (RXD) of the USART. Check to
make sure that the test fixture is installed
properly.
B.
Port IA,B,C,D] transmitted [value] received as [value]
If the value received differs from the value
transmitted, the suspected components are 6F,
7F or the USART.
70
User/Technical Manual
Advertisement
Table of Contents
