XE8806A SEMTECH [Semtech Corporation], XE8806A Datasheet - Page 59

• Manufacturer Part Number: XE8806A
• Description: Ultra Low-Power Low-Voltage
• Manufacturer: SEMTECH [Semtech Corporation]

9.1
The XE8000 chips support 8 event sources, divided into 2 levels of priority.
9.2
An event is different from an interrupt in that it does not modify the program counter (PC). Events are used by two
microcontroller instructions.
First of all, events are useful to wake-up the microcontroller when it is in HALT. The software execution then simply
resumes at the instruction next to the HALT instruction. The second instruction is the conditional jump on event
(JEV). The jump is executed if one of the event flags in the stat register is set. In all other cases, the occurrence of
an event has no effect.
The event handler allows 8 event sources to be managed individually. The 8 event sources are divided into 2 levels
of priority: High (4 event sources) and Low (4 event sources). Those 2 levels of priority are directly mapped to
those supported by the CoolRisc® (EV0and IN1; see CoolRisc documentation for more information).
Additional functions are given that allow fast detection of the highest priority event that has been activated.
9.3
The addresses given in Table 9-1 are the default values and may be different in some products.
© Semtech 2006
Features
Overview
Register map
7
6
5
4
3
2
1
0
pos.
RegEvn[7]
RegEvn[6]
RegEvn[5]
RegEvn[4]
RegEvn[3]
RegEvn[2]
RegEvn[1]
RegEvn[0]
RegEvn
r
c1
r
c1
r
c1
r
c1
r
c1
r
c1
r
c1
r
c1
rw
Table 9-1: EVN handler registers.
0 nresetglobal
0 nresetglobal
0 nresetglobal
0 nresetglobal
0 nresetglobal
0 nresetglobal
0 nresetglobal
0 nresetglobal
Register name
RegEvnPriority
Table 9-2: RegEvn
RegEvnEvn
RegEvnEn
RegEvn
reset
9-2
event #7 (high priority)
clear event #7 when written 1
event #6 (high priority)
clear event #6 when written 1
event #5 (high priority)
clear event #5 when written 1
event #4 (high priority)
clear event #4 when written 1
event #3 (low priority)
clear event #3 when written 1
event #2 (low priority)
clear event #2 when written 1
event #1 (low priority)
clear event #1 when written 1
event #0 (low priority)
clear event #0 when written 1
function
XE8806A/XE8807A
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