Digi NS7520 manual A p t e r 4 B B u s M o d u l e

Exception vector table	33
Detail of ARM exceptions	34
Entering and exiting an exception (software action)	37
Hardware Interrupts	39
FIRQ and IRQ lines	39
Interrupt controller	39
Interrupt sources	40
C h a p t e r 4 : B B u s M o d u l e	43
BBus masters and slaves	44
Cycles and BBus arbitration	44
Address decoding	45
C h a p t e r 5 : S Y S M o d u l e	47
Signal description	48
JTAG support	48
ARM debug	49
System clock generation (NS7520 clock module)	49
External oscillator vs. internal PLL circuit	49
NS7520 clock module block diagram	50
Using the external oscillator	50
External oscillator mode hardware configuration	51
Using the PLL circuit	52
PLL mode hardware configuration	52
Setting the PLL frequency	54
PLL Settings register: Setting the PLL frequency on bootup	54
PLL Control register: Setting the PLL frequency with the PLL Control
register	57
Reset circuit sources	59
NS7520 bootstrap initialization	60
C h a p t e r 6 : G E N M o d u l e	61
Module configuration	62
GEN module hardware initialization	62
GEN module registers	63

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