Datasheet

Table Of Contents
Section 15 Asynchronous Event Counter (AEC)
Rev. 2.00 Jul. 04, 2007 Page 327 of 692
REJ09B0309-0200
15.3.6 Event Counter H (ECH)
ECH is an 8-bit read-only up-counter that operates as an independent 8-bit event counter. ECH
also operates as the upper 8-bit up-counter of a 16-bit event counter configured in combination
with ECL. When word access is performed for ECH, the upper 8 bits and lower 8 bits of a 16-bit
event counter can be read from in one bus cycle.
Bit Bit Name
Initial
Value
R/W Description
7 ECH7 0 R
6 ECH6 0 R
5 ECH5 0 R
4 ECH4 0 R
3 ECH3 0 R
2 ECH2 0 R
1 ECH1 0 R
0 ECH0 0 R
Either the external asynchronous event AEVH pin, φ/2,
φ/4, or φ/8, or the overflow signal from lower 8-bit
counter ECL can be selected as the input clock source.
ECH can be cleared to H'00 by the CRCH bit in
ECCSR.
15.3.7 Event Counter L (ECL)
ECL is an 8-bit read-only up-counter that operates as an independent 8-bit event counter. ECL
also operates as the upper 8-bit up-counter of a 16-bit event counter configured in combination
with ECH. When word access is performed for ECL, the upper 8 bits and lower 8 bits of a 16-bit
event counter can be read from in one bus cycle.
Bit Bit Name
Initial
Value
R/W Description
7 ECL7 0 R
6 ECL6 0 R
5 ECL5 0 R
4 ECL4 0 R
3 ECL3 0 R
2 ECL2 0 R
1 ECL1 0 R
0 ECL0 0 R
Either the external asynchronous event AEVL pin, φ/2,
φ/4, or φ/8 can be selected as the input clock source.
ECL can be cleared to H'00 by the CRCL bit in ECCSR.