8-4
Internal Displays
Cat. No. 670 (Video board)
The Cat. No. 670 has two LEDs which indicate which Digital Soundhead is being read.
DS2 (green) indicates Projector 1, DS1(yellow) indicates Projector 2. These LEDs should
match the equivalent LEDs on the Cat. No. 611 CPIO card.
Cats. No. 671 (Dual DSP boards)
The Cat. No. 671 cards responsible for resampling and sync finding (slots 13 and 14)
display sync found on their LEDs. The 8 LEDs from top to bottom display sync found as
follows:
Upper Left found first pass
Upper Right found first pass
Lower Left found first pass
Lower Right found first pass
Upper Left found at all
Upper Right found at all
Lower Left found at all
Lower Right found at all
A red LED above each group of eight green LEDs indicates will be lit during powerup
and reset, and will go out indicating normal operation. Any red LED lighted on either
Cat. No.671 board during operation indicates a fault in that board. Normally, this will
cause the Cat. No. 673 System Services card to reset the system.
Cat. No. 673 (System Services Board)
The Cat. No. 673 card in slot 15 has a single LED (Block Error) which will light whenever
an uncorrectable block of data on the film is detected. Another single LED (Fault) above
it indicates a fault condition on the System Services board.
7 segment LED display
This displays system status. A normal power up sequence will display C,r,L,—, with the
C
and r states going by almost too fast to see, the L state taking a few seconds, and a
successful load being indicated by the dash.
Normal display during power up
C
Performing checksum on Flash Rom contents—displays briefly (about 1/10 second)
r
Resetting all cards in the DA20 (1/2 second)
L
Loading system code (a few seconds)
—
Successful system load, film not running
If the system does not load successfully, see Displays Indicating Trouble section below.
Normal display error rate
With film running, there will be a continuous display of error rate. Error rate is indicative
of relative film wear and alignment. Rates of 1 up to 8 are still correctable by the error
correction circuitry. Low numbers indicate low error rate, higher numbers indicate
higher error rate, mid-range is typical
. A right hand decimal point is used to display
intermediate values of error rate, giving higher resolution to the display (5. is equivalent
to 5-1/2). Uncorrectable data will cause a display of “F.”
