PNX1301EH NXP Semiconductors, PNX1301EH Datasheet - Page 268

• Manufacturer Part Number: PNX1301EH
• Manufacturer: NXP Semiconductors

Specifications of PNX1301EH

• Lead Free Status / RoHS Status: Not Compliant

PNX1300/01/02/11 Data Book
are shifted out. Finally the register is ‘updated’ with the
new n bits shifted in.
Note: when a register is scanned, its old value is shifted
out of TDO. The new value shifted in via TDI is written to
the register at the update state. Hence, scan in/out in-
volve the same steps. This also means that reading a
register via JTAG destroys its contents unless otherwise
stated. We can specify some registers as read-only via
JTAG so that when the controller transitions to update
state for the read-only register, the update has no effect.
Sometimes, read-write registers are needed (for exam-
ple, control registers used for handshake) which can be
read non-destructively. In such cases, the value shifted
in determines whether the old value is ‘remembered’ or
something else happens.
18-2
Figure 18-1. State diagram of TAP controller
0
1
Test Logic
Reset
Run-Test/
Idle
PRELIMINARY SPECIFICATION
0
1
1
0
Select
DR Scan
Capture
DR
Shift
Exit1
DR
Pause
DR
Exit2
DR
Update
DR
DR
1
0
0
1
1
1
0
0
18.2.2
PNX1300 uses a 5-bit instruction register. The unspeci-
fied opcodes are private and their effects are undefined.
Table 18-1
Table 18-1. JTAG instruction encoding
Encoding
1
00000
00001
10000
10001
1
11111
0
0
PNX1300 JTAG Instruction Set
lists the JTAG instructions.
EXTEST
SAMPLE/PRELOAD Select (dummy) boundary
BYPASS
RESET
SEL_DATA_IN
Instruction name
1
0
Select
IR Scan
Capture
IR
Shift
IR
Exit1
IR
Pause
IR
Exit2
IR
Update
IR
1
Philips Semiconductors
Select (dummy) boundary
scan register
scan register
Select bypass register
Reset TriMedia to power
on state
Select DATA_IN register
0
0
1
1
1
0
0
1
1
Action
0
0