Hardware manual

Rev. 3.0, 09/98, page 160 of 361
8.1.2 Block Diagram
Figure 8.1 shows a block diagram of one channel in the 8-bit timer module. The other channel is
identical.
External
clock source
TMCI
TMO
TMRI
Internal
clock sources
Channel 0 Channel 1
Ø/2
Ø/8
Ø/32
Ø/64
Ø/256
Ø/1024
Ø/2
Ø/8
Ø/64
Ø/128
Ø/1024
Ø/2048
Clock
Overflow
Clear
Compare-match B
Clock select TCORA
Comparator A
TCNT
Comparator B
Module data bus
Bus interface
TCORB
TCSR
TCR
Internal
data bus
CMIA
CMIB
OVI
Interrupt signals
TCR
TCSR
TCORA
TCORB
TCNT
: Timer Control Register (8 bits)
: Timer Control Status Register (8 bits)
: Time Constant Register A (8 bits)
: Time Constant Register B (8 bits)
: Timer Counter
Compare-match A
Control
logic
Figure 8.1 Block Diagram of 8-Bit Timer