DS2182 DALLAS [Dallas Semiconductor], DS2182 Datasheet - Page 8

• Manufacturer Part Number: DS2182
• Description: T1 Line Monitor
• Manufacturer: DALLAS [Dallas Semiconductor]

FECR: FRAME ERROR COUNT REGISTER Figure 7
MSB
The Frame Error Count Register (FECR) is an 8-bit pre-settable counter that records individual frame bit
errors. In the 193E mode (RCR2.4 = 1), the FECR records bit errors in the FPS framing pattern
(001011). In the 193S mode (RCR2.4 = 0), the FECR records bit errors in both the FT (101010) and FS
(001110) framing patterns if RCR1.3 is set. If RCR1.3 is cleared, then the FECR only records bit errors in
the FT pattern. This 8-bit counter saturates at 255 and generates an interrupt for each occurrence after
saturation if RIMR2.3 is set. The count is disabled during a loss of sync condition (RLOS = 1).
RSR1: RECEIVE STATUS REGISTER 1 Figure 8
MSB
NOTE:
1. Alarm 8ZD and 16ZD are cleared on the next occurrence of a 1 at RPOS and RNEG.
SYMBOL
SYMBOL
B8ZSD
FE7
8ZD
COFA
RYEL
RLOS
16ZD
FFE0
RCL
RBL
8ZD
FE7
16ZD
FE6
POSITION
POSITION
FECR.7
FECR.0
RSR1.7
RSR1.6
RSR1.5
RSR1.4
RSR1.3
RSR1.2
RSR1.1
RSR1.0
RCL
FE5
NAME AND DESCRIPTION
MSB of frame error count
LSB of frame error count
NAME AND DESCRIPTION
8 Zero Detect. Set when a string of eight consecutive 0s has
been received at RPOS and RNEG.
16 Zero Detect. Set when a string of 16 consecutive 0s has
been received at RPOS and RNEG.
Receive Carrier Loss. Set when a string of 192 consecutive 0s has
been received at RPOS and RNEG. Cleared when 14 or more ones
out of 112 possible bit positions are received.
Receive Yellow Alarm. Set when yellow alarm is detected. The
format of yellow alarm is determined by RCR2.3 and RCR2.4.
Receive Loss of Sync. Set when resync is in progress.
B8ZS Code Word Detect. Set when a B8ZS code word is
received at RPOS and RNEG independent of whether the B8ZS
mode is enabled or not (RCR2.2).
Receive Blue Alarm. Set when over a 3 ms window, 5 or less
zeros are received. Cleared when over a 3 ms window, 6 or more
zeros are received.
Change of Frame Alignment. Set when the last resync resulted in
a change of frame or multiframe alignment.
RYEL
FE4
8 of 25
RLOS
FE3
B8ZSD
FE2
RBL
FE1
LSB
LSB
COFA
DS2182A
FE0