
Preliminary Information
MT9071
59
8.4.2
The Bypass Register
The Bypass Register is a single stage shift register that provides a one-bit path from TDI to its TDO.
8.4.3
The Boundary-Scan Register
The Boundary-Scan Register (BSR) provides an interface between the MT9071 core logic and the MT9071
input and output pins. This interface is controlled by the TAP Controller and Instruction Register. The BSR
provides status of all digital input, output and bi-directional pins and control over all digital output and bi-
directional pins. Power pins, analog pins, oscillator pins and test pins are not included in the chain. The BSR
maps to the remaining pins. Each input pin maps to one BSR bit (input cell), each output pin maps to one or
two BSR bits (output and enable cells), and each bi-directional pin maps to three BSR bits (input, output and
enable cells). Bit 0 of the BSR is the last bit in the JTAG chain and the first bit clocked out. The JTAG chain
starts at DSTo[0] and moves counterclockwise around the chip finishing at the RXBF[3] pin (see Table 16 -
JTAG Boundary-Scan Register).
8.5
Boundary Scan Description Language (BSDL) File
A Boundary Scan Description Language (BSDL) file is available for the MT9071 JTAG implementation. This
ASCII (text) file provides all the information required for a JTAG test system to access the MT9071’s boundary
scan circuitry.
9.0
Common Channel Signaling (CCS) Operation
In CCS, an E1 PCM30 timelsot or a T1 DS0 channel is typically used to carry signaling information for all
channels in a framed and formatted data packet according to some high level data link control method. One
such method is the Link Access Procedure on the D-Channel (LAPD) ISDN protocol specified by CCITT.
Other protocols include non-ISDN protocols such as the High Level Data Link Control (HDLC) and the LAPB
Version
Part Number
Manufacturer Identity
LSB=1
Marketing Revision
(4 bits)
A
0000
0
Marketing Number
(16 bits)
9071
1001 0000 0111 0001
9 0 7 1
Mitel
(11 bits)
Mitel
0001 0100 101
LSB
(1 bit)
LSB=1
1
1 4 B
0 9 0 7 1 1 4 B
Table 15 - JTAG MT9071 Identification Register
Device Pin
Boundary-Scan Register Bits (0 to 117)
Name
Type
Cell #
Enable Register Bit
Output Register Bit
Input Register Bit
When this control/status bit
is one, the corresponding
pin is in a high impedance
state. When zero, the
corresponding pin operates
normally.
0
When this control/status bit
is one, the corresponding
pin is high. When zero, the
corresponding pin is low.
When this status bit is one,
the corresponding pin is
high. When zero, the
corresponding pin is low.
DSTo[0]
output
The sequence continues around the chip. Refer to the BSDL file for BSR bit mapping.
output
72
NA
Table 16 - JTAG Boundary-Scan Register
1
1
NA
RXBF[3]
117
NA