Table 20. jtag instructions and idcode, Cs5376a – Cirrus Logic CS5376A User Manual

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CS5376A

76

DS612F4

21.2.1 JTAG Reset

As required by the IEEE 1149.1 specification, the
JTAG TRST signal is independent of the CS5376A
RESET signal. In systems not using the JTAG port,
TRST should be connected to ground. In systems
using the JTAG port, TRST and RESET should be
independently driven to provide reset capability
during boundry scan.

21.2.2 TAP Controller

The test access port (TAP) controller manages
commands and data through the boundary scan
chain. It supports the four JTAG instructions and
contains the IDCODE listed in Table 20.

The TAP controller also implements the 16 JTAG
state assignments from the IEEE 1149.1 specifica-
tion, which are sequenced using TMS and TCK.

21.2.3 Boundary Scan Cells

The CS5376A JTAG test port provides access to all
device pins via internal boundary scan cells. When
the JTAG port is disabled, boundary scan cells are
transparent and do not affect CS5376A operation.

When the JTAG port is enabled, boundary scan
cells can write and read each pin independent of
CS5376A operation.

Boundary scan cells are serially linked to create a
scan chain around the CS5376A controlled by the
TAP controller. Table 21 lists the scan cell map-
ping of the CS5376A.

JTAG Instructions

Encoding

BYPASS

11

EXTEST

00

IDCODE

01

SAMPLE / PRELOAD

10

JTAG IDCODE

Components

Encoding

Revision

0x10000000

Device ID

0x05376000

Manufacturer ID

0x000000C9

CS5376A IDCODE

0x153760C9

Table 20. JTAG Instructions and IDCODE

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