NTRB21DTI/PRI/DCH TMDI card Page459 of 544
Option11C and 11C Mini TechnicalReference Guide
Shelf slot assignment
On non-ECM system cabinets, the NTAK20 may be placed in slots 1-9. On
cabinets NTAK11Dx and NTAK11Fx, the active NTAK20 must be placed in
slots 1-3 (slots 4-10 may not be used).
Physical description
The NTRB21 card uses a standard IPE-sized (9.5" by 12.5"), multi-layer
printed circuit board with buried power and ground layers. It is keyed to
prevent insertion in slot 10. The clock controller daughterboard is fastened by
standoffs and connectors.
The NTRB21 card has seven faceplate LEDs. The first five LEDs are
associated with the N TRB21 card, the rem aining two LEDs are associated
with the clock controller and DCHI daughterboards.
In general, the first five LEDs o perate as follows:
•During system power up, the LEDs are on.
•When the self-test is in progress, the LEDs flash on and off three times,
then go into their appropriate states, as shown in Table143