cx28394 Conexant Systems, Inc., cx28394 Datasheet - Page 225

• Manufacturer Part Number: cx28394
• Description: Quad/x16/octal-t1/e1/j1 Framers
• Manufacturer: Conexant Systems, Inc.

CX28394/28395/28398
Quad/x16/Octal—T1/E1/J1 Framers
DEBOUNCE
FRZ_OFF/FRZ_ON
100054E
Debounce Receive ABCD Signaling—Applicable only to those channels where signaling
stack is enabled (SIG_STK; addr 180–19F). Output signaling buffer (RSIG) updates for these
channels are evaluated after D-bit signaling is received. New signaling is placed into RSIG and
STACK buffers only if the RSIG input and output values differ. DEBOUNCE filters single bit
errors on ABCD signaling. This is accomplished by comparing incoming ABCD bits on a
bit-by-bit basis with current buffered input and output ABCD bits and inverting the update
signaling bit value when incoming and output bits are equal. However, these differ from the
buffered input value below. At the end of each multiframe, the entire input ABCD value is
copied to the output ABCD value.
Manual Signaling Update and SIGFRZ Output—Allows the processor to manually control
updates of the receive signaling buffer [RSIGn; addr 1A0–1BF], the signaling stack [addr
0DA], and the SIGFRZ output pin. FRZ_ON and FRZ_OFF control the SIGFRZ pin’s output
state, but do not affect normal operations of the SIGFRZ interrupt [ISR7; addr 004]. Receive
ABCD input signaling is placed into STACK and RSIG buffers according to the modes shown
below. Stack updates are individually enabled on a per-channel basis according to SIG_STK
[addr 180–19F].
0 = no effect
1 = debounce receive ABCD signaling
NOTE(S):
buffer space coincident with the D-bit update.
Sig Input
FRZ_ON
0
0
0
0
1
1
1
1
X
X
0
0
0
1
Normal (non-debounced) signaling always transfers ABCD input to ABCD output
Current Bit I/O
FRZ_OFF
0
0
0
1
0
00
01
10
11
00
01
10
11
SIG_STK
Conexant
Update Bit I/O
X
X
0
1
0
1
00
00
00
01
10
11
11
11
Interrupt
SIGFRZ
X
X
X
0
1
0
Change output
Debounce
Debounce
Change output
Pin
0
1
0
0
0
1
No update
No update
ABCD Changes
No Update
ABCD Changes
No update
Notes
—
—
—
—
STACK
3.16 System Bus Registers
3.0 Registers
No Update
All ABCD
All ABCD
All ABCD
All ABCD
No update
RSIGn
3-103