Freescale Semiconductor PE Micro Cyclone Pro, Руководство пользователя

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70 Cyclone PRO User Manual
CYCLONE PRO
Figure 8-14: Advanced Settings Tab
8.3.3.1 Tpd And Tpu Timing
Tpu and Tpd will set the power-up and power-down delay (respectively)
that will be observed when power-cycling a target for entry into Monitor
Mode. These settings are only valid for devices with automatically
controlled power.
Whenever power is automatically switched off, or is manually requested
to be switched off, the software waits for an amount of time equal to the
Tpd delay time before proceeding to the connection protocol. This is
because a board or power supply may have capacitance which holds the
power up for a short time after the supply has been switched off, but the
supply voltage must reach less than 0.1v before it is turned back on if a
Power-On reset is to occur.
Whenever power is automatically switched on, or is manually requested
to be switched on, the software waits for an amount of time equal to the
Tpu delay time before attempting to contact the 68HC08 processor. This
is to allow time not only for power to be fully available, but to wait until any
reset driver has finally released the RESET line.