R01UH0822EJ0100 Rev.1.00
Page 399 of 1041
Jul 31, 2019
RX13T Group
19. Multi-Function Timer Pulse Unit 3 (MTU3c)
19.3.4
Cascaded Operation
In cascaded operation, two 16-bit counters in different channels are used together as a 32-bit counter.
There are two functions for connecting MTU1 and MTU2 to use as a 32-bit counter: cascade connection to be set when
the MTU1.TMDR3.LWA bit is 0, and cascade connection 32-bit phase counting mode to be set when the
MTU1.TMDR3.LWA bit is 1. For details on cascade connection 32-bit phase counting mode, refer to
Cascade Connection 32-Bit Phase Counting Mode
. This section describes the cascade connection function to be set
when the MTU1.TMDR3.LWA bit is 0.
This function operates when the MTU1.TMDR3.LWA bit is set to 0 and the MTU1.TCR.TPSC[2:0] bits are set so that
MTU1.TCNT counts at an overflow/underflow of MTU2.TCNT. Underflow occurs only when the MTU2 to which the
lower 16 bits allocated is in phase counting mode.
shows the register combinations used in cascaded operation.
Note:
When phase counting mode is set for MTU1, the count clock setting is invalid and the counters operate
independently in phase counting mode.
For simultaneous input capture of MTU1.TCNT and MTU2.TCNT during cascaded operation, additional input capture
input pins can be specified by the input capture control register (TICCR). The input-capture condition is of edges in the
signal produced by taking the logical OR of the input level on the main input pin and the input level on the added input
pin. Accordingly, if either is at the high level, a change in the level of the other will not produce an edge for detection.
For details, refer to
(4), Cascaded Operation Example (c)
. For input capture in cascade connection, refer to
19.6.21, Simultaneous Input Capture in MTU1.TCNT and MTU2.TCNT in Cascade Connection
.
shows the TICCR setting and input capture input pins.
Table 19.47
Cascaded Combinations
Combination
Upper 16 Bits
Lower 16 Bits
MTU1 and MTU2
MTU1.TCNT
MTU2.TCNT
Table 19.48
TICCR Setting and Input Capture Input Pins
Target Input Capture
TICCR Setting
Input Capture Input Pin
Input capture from MTU1.TCNT to
MTU1.TGRA
I2AE bit = 0 (Initial value)
MTIOC1A
I2AE bit = 1
MTIOC1A, MTIOC2A
Input capture from MTU1.TCNT to
MTU1.TGRB
I2BE bit = 0 (Initial value)
MTIOC1B
I2BE bit = 1
MTIOC1B, MTIOC2B
Input capture from MTU2.TCNT to
MTU2.TGRA
I1AE bit = 0 (Initial value)
MTIOC2A
I1AE bit = 1
MTIOC2A, MTIOC1A
Input capture from MTU2.TCNT to
MTU2.TGRB
I1BE bit = 0 (Initial value)
MTIOC2B
I1BE bit = 1
MTIOC2B, MTIOC1B