
AMDebug™ Technology
Élan™SC520 Microcontroller User’s Manual
26-5
26.3.3
Locating the Connector on the Target System
Because the AMDebug port can contain high-frequency signals, position the connector as
close to the processor as possible. However, allowances should be made for the physical
requirements of the AMDebug control unit. For systems that support JTAG-based boundary
scanning, a jumper block should be provided for isolating from the rest of the JTAG scan
chain (see Figure 26-5) the connection from the AMDebug port to the processor. This
jumper is not required by systems that only use JTAG to support AMDebug technology.
When AMDebug technology debugging is not used, the jumpers can be set to connect the
processor with the other devices forming the scan chain.
Figure 26-5
Locating the Target Connector
The target board should be equipped with pullup and pulldown resistors, as shown in
Figure 26-5. The signal lines driven by the female cable connector should be three-stated
before connection is established. The connection device can sense the required high volt-
age by sampling the VCC signal pin before driving the AMDebug port.
JTAG_TCK
JTAG_TMS
JTAG_TDI
JTAG_TRST
SYSRESET
CMDACK
BR/TC
STOP/TX
TRIG/TRACE
JTAG_TDO
GND
10 k
Ω
33
Ω
33
Ω
33
Ω
10 k
Ω
VCC
Jumper setting when
not used for debugging
JTAG_TDI on next
chip in chain
JTAG_TDO on previous
chip in chain
ÉlanSC520
Microcontroller
Bus
Содержание Elan SC520
Страница 1: ...lan SC520 Microcontroller User s Manual Order 22004A...
Страница 4: ...iv lan SC520 Microcontroller User s Manual...
Страница 28: ...Introduction xxviii lan SC520 Microcontroller User s Manual...
Страница 42: ...Architectural Overview 1 14 lan SC520 Microcontroller User s Manual...
Страница 78: ...System Initialization 3 22 lan SC520 Microcontroller User s Manual...
Страница 108: ...Clock Generation and Control 5 10 lan SC520 Microcontroller User s Manual...
Страница 118: ...Reset Generation 6 10 lan SC520 Microcontroller User s Manual...
Страница 148: ...System Arbitration 8 24 lan SC520 Microcontroller User s Manual...
Страница 214: ...SDRAM Controller 10 36 lan SC520 Microcontroller User s Manual...
Страница 230: ...Write Buffer and Read Buffer 11 16 lan SC520 Microcontroller User s Manual...
Страница 288: ...GP Bus DMA Controller 14 22 lan SC520 Microcontroller User s Manual...
Страница 316: ...Programmable Interval Timer 16 8 lan SC520 Microcontroller User s Manual...
Страница 328: ...Software Timer 18 4 lan SC520 Microcontroller User s Manual...
Страница 346: ...Real Time Clock 20 12 lan SC520 Microcontroller User s Manual...
Страница 360: ...UART Serial Ports 21 14 lan SC520 Microcontroller User s Manual...
Страница 414: ...AMDebug Technology 26 8 lan SC520 Microcontroller User s Manual...