XRT83L38ES Exar, XRT83L38ES Datasheet - Page 31

• Manufacturer Part Number: XRT83L38ES
• Description: Peripheral Drivers & Components - PCIs
• Manufacturer: Exar

Specifications of XRT83L38ES

• Product Category: Peripheral Drivers & Components - PCIs
• Rohs: yes

REV. 1.0.2
ARBITRARY PULSE GENERATOR FOR T1 AND E1
The arbitrary pulse generator divides the pulse into eight individual segments. Each segment is set by a 7-Bit
binary word by programming the appropriate channel register. This allows the system designer to set the
overshoot, amplitude, and undershoot for a unique line build out. The MSB (bit 7) is a sign-bit. If the sign-bit is
set to “1”, the segment will move in a positive direction relative to a flat line (zero) condition. If this sign-bit is set
to “0”, the segment will move in a negative direction relative to a flat line condition. A pulse with numbered
segments is shown in
N
TRANSMITTER
DIGITAL DATA FORMAT
Both the transmitter and receiver can be configured to operate in dual or single-rail data formats. This feature is
available under both Hardware and Host control modes, on a global basis. The dual or single-rail data format
is determined by the state of the SR/DR pin in Hardware mode or SR/DR interface bit in the Host mode. In
single-rail mode, transmit clock and NRZ data are applied to TCLK_n and TPOS_n/TDATA_n pins respectively.
In single-rail and Hardware mode the TNEG_n/CODES_n input can be used as the CODES function. With
TNEG_n/CODES_n tied “Low”, HDB3 or B8ZS encoding and decoding are enabled for E1 and T1 modes
respectively. With TNEG_n/CODES_n tied “High”, the AMI coding scheme is selected. In both dual or single-
rail modes of operations, the transmitter converts digital input data to a bipolar format before being transmitted
to the line.
TRANSMIT CLOCK (TCLK) SAMPLING EDGE
Serial transmit data at TPOS_n/TDATA_n and TNEG_n/CODES_n are clocked into the XRT83L38 under the
synchronization of TCLK_n. With a “0” written to the TCLKE interface bit, or by pulling the TCLKE pin “Low”,
input data is sampled on the falling edge of TCLK_n. The sampling edge is inverted with a “1” written to TCLKE
interface bit, or by connecting the TCLKE pin “High”.
F
OTE
IGURE
: By default, the arbitrary segments are programmed to 0x00h. The transmitter outputs will result in an all zero pattern
to the line. For E1 arbitrary mode, see global register 0xC0h.
11. A
RBITRARY
OCTAL T1/E1/J1 LH/SH TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
Segment
1
2
3
4
5
6
7
8
Figure
P
ULSE
11.
S
Register
EGMENT
0xn8
0xn9
0xna
0xnb
0xnc
0xnd
0xne
0xnf
A
SSIGNMENT
1
2
3
28
4
5
6
7
8
XRT83L38