Bt8370/8375/8376
3.17 System Bus Registers
Fully Integrated T1/E1 Framer and Line Interface
0DD—RAM Parity Status (PERR)
All Bt8370/8375/8376 system bus data, signaling, and controls are transferred through a set of internal RAMs
with parity error detection capabilities. Any parity error detected during RAM access is reported in PERR. Each
error event is latched active-high and held until the processor read clears PERR. Parity errors are indicative of
system clock glitches (REFCKI, TSBCKI, or RSBCKI), a failing or excessively noisy power supply, or general
circuit failure.
7
6
5
4
3
2
1
0
—
—
—
—
—
PERR_TPC
PERR_RPC
PERR_SBC
PERR_TPC
PERR_RPC
PERR_SBC
TPC (Transmit) RAM Parity Error
RPC (Receive) RAM Parity Error
SBC (Control) RAM Parity Error
0E0–0FF—System Bus Per-Channel Control (SBCn; n = 0 to 31)
7
6
5
4
3
2
1
0
—
INSERT
SIG_LP
RLOOP
RINDO
TINDO
TSIG_AB
ASSIGN
INSERT
Insert RX Signaling on RPCMO—Enables per-channel signaling insertion on RPCMO output,
where ABCD signaling is supplied by RLOCAL signaling (RPCn; addr 180–19F) or buffered
signaling [RSIGn; addr 1A0–IBF]. INSERT is a lower priority than no signaling (SIG_OFF;
addr 0D1). RSB signaling frame locations are specified by RMSYNC signal in conjunction
with the programmed frame offset [OFFSET; addr 0D8].
SIG_OFF
INSERT RLOCAL
RPCMO Inserted Signal
None
1
0
0
X
1
X
0
ABCD from RSIGn output buffer
ABCD from RPCn local buffer
1
1
SIG_LP
Local Signaling Loopback—Instructs the receiver output signaling on RSIGO to be supplied
from TSIGn buffer contents. Signaling in RPCMO (T1-robbed bit or E1-CAS) is not affected.
0 = normal
1 = local signaling loopback
RLOOP
RINDO
Local Loopback—RPCMO output data supplied from TSLIP buffer contents.
0 = normal
1 = local loopback
Activate RINDO Time Slot Indicator—Receive system bus time slots are individually marked
(active-high for 8 bits) by RINDO. SBI_OE (addr 0D0) overrides RINDO.
0 = RINDO signal inactive (low)
1 = RINDO signal active (high)
TINDO
Activate TINDO Time Slot Indicator—Transmit system bus time slots are individually marked
(active-high for 8 bits) by TINDO.
0 = TINDO inactive
1 = TINDO active
3-128
Conexant
N8370DSE