238
2. Block diagram
Figure 9.18 shows a block diagram of the asynchronous event counter.
ECCSR
ECH
ECL
IRREC
Internal data bus
OVL
OVH
CK
CK
AEVL
AEVH
: Event counter control/status register
: Event counter H
: Event counter L
: Asynchronous event input H
: Asynchronous event input L
: Event counter overflow interrupt request flag
Notation:
ECCSR
ECH
ECL
AEVH
AEVL
IRREC
Figure 9.18 Block Diagram of Asynchronous Event Counter