Datasheet

DS26521 Single T1/E1/J1 Transceiver
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Register Name:
RIOCR
Register Description:
Receive I/O Configuration Register
Register Address:
084h
Bit # 7 6 5 4 3 2 1 0
Name
RCLKINV RSYNCINV H100EN RSCLKM
RSMS RSIO RSMS2 RSMS1
RCLKINV RSYNCINV H100EN RSCLKM
—
RSIO RSMS2 RSMS1
Default 0 0 0 0 0 1 0 0
Bit 7: RCLK Invert (RCLKINV).
0 = no inversion
1 = invert RCLK as input
Bit 6: RSYNC Invert (RSYNCINV).
0 = no inversion
1 = invert RSYNC as either input or output
Bit 5: H.100 SYNC Mode (H100EN). See Section
8.8.3 for more information.
0 = normal operation
1 = RSYNC and TSSYNCIO signals are shifted
Bit 4: RSYSCLK Mode Select (RSCLKM).
0 = if RSYSCLK is 1.544MHz
1 = if RSYSCLK is 2.048MHz or IBO enabled
Bit 3: RSYNC Multiframe Skip Control (RSMS) (T1 Mode Only). Useful in framing format conversions from D4 to
ESF. This function is not available when the receive-side elastic store is enabled. RSYNC must be set to output
multiframe pulses.
0 = RSYNC will output a pulse at every multiframe
1 = RSYNC will output a pulse at every other multiframe
Bit 2: RSYNC I/O Select (RSIO). (Note: This bit must be set to zero when elastic store is disabled) The default
value for this bit is a logic 1 so that the default state of RSYNC is as an input.
0 = RSYNC is an output
1 = RSYNC is an input (only valid if elastic store enabled)
Bit 1: RSYNC Mode Select 2 (RSMS2).
T1 Mode: RSYNC pin must be programmed in the output frame mode.
0 = do not pulse double-wide in signaling frames
1 = do pulse double-wide in signaling frames
E1 Mode: RSYNC pin must be programmed in the output multiframe mode.
0 = RSYNC outputs CAS multiframe boundaries
1 = RSYNC outputs CRC-4 multiframe boundaries
In E1 mode, RSMS2 also selects which multiframe signal is available at the RMSYNC pin, regardless of the
configuration for RSYNC. When RSMS2 = 0, RMSYNC outputs CAS multiframe boundaries; when RSMS2 = 1,
RMSYNC outputs CRC-4 multiframe boundaries.
Bit 0: RSYNC Mode Select 1 (RSMS1). Selects frame or multiframe pulse when RSYNC pin is in output mode. In
input mode (elastic store must be enabled) multiframe mode is only useful when receive-signaling reinsertion is
enabled.
0 = frame mode
1 = multiframe mode