Siemens ERTEC200 Manual De Usuario

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f/MHz
t/µs
t
LOCK 
= 645 µs
35
Power-up PLL
active
Reset
300
 
 
Figure 11: Power-Up Phase of the PLL 
The lock status of the PLL is monitored by the hardware.  Loss of the input clock and PLL not locked status is signaled 
with interrupt FIQ3. The state of the PLL can also be read out in the PII_STAT_REG system control register. A filter is 
integrated at the RESET_N input, which suppresses spikes up to 5 ns.   
The SRST_N reset signal is available for the debugger. The signal is activated while RESET_N is active and the internal 
PowerOn-reset extension is running. This enables the debugger to recognize the PowerOn-reset phase.  
 
5.2.2 Hardware 
Reset 
The hardware reset is trigger
drain output). The reset is normally only activated 
by the debugger.  During the 
nal logic is reset without
ed via the bidirectional SRST_N pin (open 
active hardware-reset phase, the entire inter
 the clock system. In 
addition, the configuration and boot pins are not read in or saved, either. 
ase, the debugger can communication with
om the reset address. As with the RESET_N
eset, the boot mode that was saved during
are reset, the PowerOn/Hardware-reset bit is
cted by the triggered reset function. Th
 
software monitoring by the hardware. Monito
 watchdog is activated. Retriggering the time
gered. If the timer is not retriggered, the w
ve with the WD_RES_FREI bit. The watch
etching (PV). The watchdog reset resets the
are reset, the watchdog reset bit is set in the 
 the triggered reset function. This register can
, the watchdog event on GPIO[15] can be signa
During the hardware reset ph
 the embedded ICE logic via the JTAG interface, 
enabling a single-step trace fr
 input a filter that suppresses spikes up to 5 ns 
is also integrated here.  
For booting after a hardware r
 the PowerOn reset is used. 
During PowerON and hardw
 set in the RES_STAT_REG system control 
register, which remains unaffe
is register can be evaluated after a restart. 
5.2.3 Watchdog 
Reset
The watchdog reset involves 
ring is based on a time setting in the watchdog 
timer. This is started when the
r at a specified reload value prevents the 
watchdog reset from being trig
atchdog reset is enabled after the timer expires 
if the watchdog function is acti
dog reset is controlled in the ERTEC 200 by 
means of assignable pulse str
 complete ERTEC 200 circuit.   
As is the case with the hardw
RES_STAT_REG system control register, 
which remains unaffected by
 be evaluated after a restart. 
Via the alternative function
led to an external host processor. 
The watchdog reset also resets the IRT switch controller when the EN_WD_SOFT_RES_IRTE bit is set in the 
RES_CTRL_REG system control bit. 
For booting after a watchdog reset, the boot mode that was saved during the PowerOn reset is used. 
 
5.2.4 Software 
reset 
A software reset can be triggered in the ERTEC 200 by setting the XRES_SOFT bit in the reset control register. The 
software reset bit is set in the RES_STAT_REG system control register when the reset is triggered. The 
RES_STAT_REG system control register is unaffected by the triggered reset function and can be evaluated after restart. 
The software reset also resets the IRT switch controller when the EN_WD_SOFT_RES_IRTE bit is set in the 
RES_CTRL_REG system control bit.  
For booting after a software reset, the boot mode that was saved during the PowerOn reset is used. 
 
5.2.5 
IRT Switch Reset 
The switch module can be reset by means of a register in the IRT switch. The reset function of the switch module is 
retained until the bit is revoked again. The internal PHYs can be reset either via the RESET_N pin or by the IRT switch 
controller via PHY_RES_N. The selection of the reset used for the PHYs is specified with the PHY_RES_SEL bit in the 
PHY_CONFIG system control register. Whenever the SMI interface is not activated in the IRT switch the PHY_RES_N is 
active and, if the appropriate selection is made, maintains the PHYs in reset state (little power loss from the PHYs) for 
this phase.   
 
 
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ERTEC 200 Manual 
Technical data subject to change                                                                                                                                Version 1.1.0