LM3S818 Luminary Micro, Inc, LM3S818 Datasheet - Page 49

• Manufacturer Part Number: LM3S818
• Description: Lm3s818 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Figure 5-5. Boundary Scan Register Format
5.4.2.4
5.4.2.5
5.4.2.6
February 6, 2007
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signals are input, output, and output enable, and are arranged in that order as can be seen in the
figure. In addition to the GPIO pins, the controller reset pin, RST, is included in the chain. Because
the reset pin is always an input, only the input signal is included in the Data Register chain.
When the Boundary Scan Data Register is accessed with the SAMPLE/PRELOAD instruction, the
input, output, and output enable from each digital pad are sampled and then shifted out of the
chain to be verified. The sampling of these values occurs on the rising edge of TCK in the Capture
DR state of the TAP controller. While the sampled data is being shifted out of the Boundary Scan
chain in the Shift DR state of the TAP controller, new data can be preloaded into the chain for use
with the EXTEST and INTEST instructions. These instructions either force data out of the
controller, with the EXTEST instruction, or into the controller, with the INTEST instruction.
For detailed information on the order of the input, output, and output enable bits for each of the
GPIO ports, please refer to the Stellaris Family Boundary Scan Description Language (BSDL)
files, downloadable from www.luminarymicro.com.
APACC Data Register
The format for the 35-bit APACC Data Register defined by ARM is described in the ARM®
Cortex™-M3 Technical Reference Manual.
DPACC Data Register
The format for the 35-bit DPACC Data Register defined by ARM is described in the ARM®
Cortex™-M3 Technical Reference Manual.
ABORT Data Register
The format for the 35-bit ABORT Data Register defined by ARM is described in the ARM®
Cortex™-M3 Technical Reference Manual.
GPIO PB6
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GPIO m
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Preliminary
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RST
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GPIO m+1
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GPIO n
LM3S818 Data Sheet
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