MB90520A/520B Series
49
7.
8/16-bit Up/Down Counter/Timers 0 and 1
The 8/16-bit up/down counter/timers can operate in timer mode, up/down count mode, and phase difference
count mode.
The unit can be used as either a 2-channel
× 8-bit or 1-channel × 16-bit up/down counter/timer.
8/16-bit up/down counter/timer functions
Operation
Mode
Count Mode
Count Clock
(Count Edge)
Function of
ZIN Pin
Other Functions
8-bit
× 2-channel
mode
Timer mode
2/
φ, 4/φ
(
φ : Machine clock frequency)
Compare function
Reload function
Compare/reload function
Compare/reload prohibit
The direction of the
previous count can be
determined from the up/
down flag.
Interrupt requests can be
generated on the following
conditions :
1 : Compare match
2 : Underflow or overflow
3 : Count direction
change
Up/down count
mode
Counts up on detecting speci-
fied edge on the AIN pin.
Counts down on detecting spec-
ified edge on the BIN pin.
Counter clear
function
Gate function
Phase
difference count
mode
(multiply by 2)
Reads the AIN pin input level on
detecting a rising or falling edge
on the BIN pin and counts up or
counts down.
Counter clear
function
Gate function
Phase
difference count
mode
(multiply by 4)
Reads the AIN pin input level on
detecting a rising or falling edge
on the BIN pin and counts up or
counts down. Similarly, reads
the BIN pin input level on detect-
ing a rising or falling edge on the
AIN pin and counts up or counts
down.
Counter clear
function
Gate function
16-bit
× 1-channel
mode
Timer mode
2/
φ, 4/φ
(
φ : Machine clock frequency)
Up/down count
mode
Counts up on detecting speci-
fied edge on the AIN pin.
Counts down on detecting spec-
ified edge on the BIN pin.
Counter clear
function
Gate function
Phase
difference count
mode
(multiply by 2)
Reads the AIN pin input level on
detecting a rising or falling edge
on the BIN pin and counts up or
counts down.
Counter clear
function
Gate function
Phase
difference count
mode
(multiply by 4)
Reads the AIN pin input level on
detecting a rising or falling edge
on the BIN pin and counts up or
counts down. Similarly, reads
the BIN pin input level on detect-
ing a rising or falling edge on the
AIN pin and counts up or counts
down.
Counter clear
function
Gate function