Startup Timing
7-9
System Timing
7.3
Startup Timing
When power is turned on, or a reset is initiated, a power-on delay circuit is im-
plemented with a 17-bit counter to guarantee that the power supply has
reached a certain level, and the oscillator is stable. The delay introduced by
this counter is:
24MHz System clock: (2
17
− 1)
S
(1/24)
S
10
−6
= 0.005461s
1MHz System clock: (2
17
− 1)
S
10
−6
= 0.131071s
7.3.1
Normal-Mode Power-On Reset Timing
EA is sampled during power-on reset for code security purposes. PSEN and
ALE are internally pulled up during reset for serial and parallel flash program-
ming mode detection.
After the reset sequence, PSEN and ALE signals are driven by the CPU, and
the internal pull up resistors are removed for saving power.
7.3.2
Flash Programming Mode Power-On Reset Timing
EA is ignored for serial and parallel flash programming operations.
Figure 7−5. Reset Timing
Figure 7−6. Parallel Flash Programming Power-On Timing (EA is ignored)
Содержание MSC1210
Страница 1: ... December 2002 User s Guide SBAU077 ...
Страница 149: ...Digital Filter 12 13 Analog to Digital Converter Figure 12 5 Filter Frequency Responses ...
Страница 162: ...12 26 ...
Страница 234: ...Timers 17 6 Figure 17 4 Timer Counter 1 Mode 1 Figure 17 5 Interrupt System ...
Страница 273: ...Serial Port I O 17 45 Keil Simulator Figure 17 19 Clock Control Peripheral Figure 17 20 USART0 Preipheral ...
Страница 282: ...C 4 ...