3.0 Electrical Interfaces
Fusion 878A
3.7 JTAG Interface
PCI Video Decoder
3-30
Conexant
100600B
3.7.3 Optional Device ID Register
The Fusion 878A has the optional device identification register defined by the
JTAG specification as displayed in
. This register contains information
concerning the revision, actual part number, and manufacturer’s identification
code specific to Conexant. This register can be accessed through the TAP
controller via an optional JTAG instruction.
3.7.4 Verification with the TAP Controller
A variety of verification procedures can be performed through the TAP controller.
With a set of four instructions, the Fusion 878A can verify board connectivity at
all digital interfaces and pins. The instructions (listed below) are accessible by
using a state machine standard to all JTAG controllers:
•
Sample/Preload
•
Extest
•
ID Code
•
Bypass (see
)
Refer to the IEEE Std 1149.1 specification for details concerning the
Instruction Register and JTAG state machine (http://standards.ieee.org/).
Conexant has created a BSDL with the AT&T BSD™ Editor. For JTAG
testing, obtain a disk with an ASCII version of the complete BSDL file by
contacting your local Conexant sales office.
Table 3-10. Device Identification Register
Version
Part Number
Manufacturer ID
X X X X 0 0 0 0 0 0 1 1 0 1 0 1 0 0 0 0 0 0 0 1 1 0 1 0 1 1 0 1
0
0x036E
0x0D6
4 Bits
16 Bits
11 Bits
Figure 3-16. Instruction Register
TDI
TDO
EXTEST
0
0
0
Sample/Preload
0
0
1
ID Code
0
1
0
Bypass
1
1
1
879A_047