Sierra Video 507125 - Manual (Page 6)

Sierra Video Systems SmartLinx Bus Adapter busadap.doc
6
Figure 4: Rotary Switch S4
3. LEDs
The host adapter has a set of 10 LEDS in one corner of the board, plus an additional LED inside the reset
switch. The following sections describe their use.
Figure 5: LEDs
3.1 Startup Diagnostics and LEDs During Startup
When the bus adapter is powered on, the first thing it does is perform a series of diagnostic tests of its flash
memory and RAM memory. The progress of these tests is indicated by the LEDs, as follows:
1. LEDs 1-7 and the RESET LED are flashed on and off rapidly for one second. This indicates that the
bus adapter is alive and the software is starting up.
2. LED #1 is turned on, then the longword checksum of the two FLASH memory devices (U7 and U8) is
computed. The result should be 0. If not, LED #1 is flashed for about three seconds, then normal
operation is attempted.
3. LEDs #2 and #3 are turned on, then a random test pattern is written to the two static RAMs (U9 and
U11) and then read back to verify. If the pattern verifies incorrectly, the LED of the RAM that verified
incorrectly is flashed for about three seconds. LED #2 is flashed if the even byte (U11) is bad, and LED
#3 is flashed if the odd byte (U9) is bad. Both will be flashed if both bytes are bad at the first incorrect
word verification. After flashing, normal operation is attempted.
4. The value of the first two rotary switches, S1 and S2, is displayed on LEDs 1-7 and the RESET LED for
one second. Then, the value of the second two rotary switches, S3 and S4, is displayed on the LEDS for
one second. Then, the value of the 8 DIP switches is displayed on the LEDs for one second. Then, LED
#4 is turned on for one second to indicate that all tests passed, and normal operation begins.
- 8V OK
+8V OK
+5V OK
7
6
5
4
3
2
1
0
2
1 F
E
3
D
C 4
5
6
7 8 9
A
B
S4
RESET
Any rotary switch change results in
an immediate automatic reset.