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5.7.2
Description of the Test
Functions
Testing the user memory
Testing the BASP signal
Testing the hardware clock
CPU 948 Programming Guide
C79000-G8576-C848-04
(During OVERALL RESET, without time slice)
The user memory is tested during an OVERALL RESET. This test
checks the user memory, the byte areas, the flags and process images.
During the test, the whole area (including the byte areas) are written
with a test pattern and then checked to make sure that they match. At
the end of the test, the area is written with zeros.
Note
The user memory test takes time to complete
- CPU 948-1 (640 Kbytes)
- CPU 948-2 (1 664 Kbytes)
(In the STOP mode, without time slice)
This test checks whether a BASP signal is output by the CPU. The test
function runs in the stop loop. The BASP signal is then read cyclically.
If an error is detected, an entry is made in the error buffer. At the next
START-UP, OB 36 (error in self-test) is called, if it exists. If OB 36 is
loaded and contains an STP operation, the START-UP is aborted.
Otherwise, the CPU changes to the cyclic mode.
(During START-UP, however, only in CPU COLD RESTART;
without time slice)
This test is made before OB 20 is called and takes one second.
The current time is retained; existing timed jobs (clock-controlled
interrupts - OB 9) on the other hand are deleted.
Self-Test
approx. 5 seconds
approx. 22 seconds
5 - 35
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