21-4
MCF5272 User’s Manual
Boundary Scan Register
Figure 21-2. TAP Controller State Machine
21.4 Boundary Scan Register
The boundary scan register contains bits for all device signal and clock pins and associated
control signals. Bidirectional pins include a single scan bit for data (IO.Cell) as shown in
Figure 21-6. These bits are controlled by an enable cell, shown in Figure 21-5. The control
bit value determines whether the bidirectional pin is an input or an output. One or more
bidirectional data bits can be serially connected to a control bit as shown in Figure 21-7.
Note that when bidirectional data bits are sampled, bit data can be interpreted only after
examining the I/O control bit to determine pin direction.
Open-drain bidirectional bits require separate input and output cells as no direction control
is available from which to determine signal direction. Programmable open-drain signals
also have an enable cell (XXX.de) to select whether the pin is open drain or push-pull.
Signals with pull-up or pull-down resistors have an associated enable cell (XXX.pu); one
enable cell can control multiple resistors.
TEST LOGIC
RESET
RUN-TEST/IDLE
SELECT-DR_SCAN
CAPTURE-DR
SELECT-IR_SCAN
CAPTURE-IR
SHIFT-DR
SHIFT-IR
EXIT1-DR
EXIT1-IR
PAUSE-DR
PAUSE-IR
EXIT2-DR
UPDATE-DR
EXIT2-IR
UPDATE -IR
1
0
1
1
0
1
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
0
0
0
0
0
1
Содержание DigitalDNA ColdFire MCF5272
Страница 1: ...MCF5272UM D Rev 0 02 2001 MCF5272 ColdFire Integrated Microprocessor User s Manual ...
Страница 38: ...xxxviii MCF5272 User s Manual TABLES Table Number Title Page Number ...
Страница 58: ...1 10 MCF5272 User s Manual MCF5272 Specific Features ...
Страница 90: ...2 42 MCF5272 User s Manual Exception Processing Overview ...
Страница 96: ...3 6 MCF5272 User s Manual MAC Instruction Execution Timings ...
Страница 158: ...5 46 MCF5272 User s Manual Motorola Recommended BDM Pinout ...
Страница 184: ...7 12 MCF5272 User s Manual Interrupt Controller Registers ...
Страница 338: ...13 44 MCF5272 User s Manual Application Examples ...
Страница 414: ...18 6 MCF5272 User s Manual PWM Programming Model ...
Страница 452: ...19 38 MCF5272 User s Manual Power Supply Pins ...
Страница 482: ...20 30 MCF5272 User s Manual Reset Operation ...
Страница 492: ...21 10 MCF5272 User s Manual Non IEEE 1149 1 Operation ...
Страница 548: ...INDEX Index 12 MCF5272 User s Manual ...