M30222 Datasheet, PDF (82/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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Specifications in this manual are tentative and subject to change
MITSUBISHI MICROCOMPUTERS
M30222 Group
Rev. G
Timer A
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(5) Real-time port mode
When Real-time port output is selected, the data previously written to the port Pm latch is clocked into
the Real-time port latch each time the corresponding Timer Ai underflows. The Real-time port data is
written to the corresponding port Pm register. When the Real-time port mode select bit changes state
from "0" to "1", the value of the Real-time port latch becomes "0", which is ouput from the correspond-
ing pin. It is when Timer Ai underflows first that the Real-time port data is ouput. If the Real-time port
data is modified when the Real-time port function is enabled, the modified value is output when Timer
Ai underflows next time. The port functions as an ordinary port when the Real-time port function is
disabled.
Make sure Timer Ai for Real-time port output is set for timer mode, and is set to have "no gate
function" using the gate function select bit. Also, before setting the Real-time port mode select bit to
"1", temporarily turn off Timer Ai and write its set value to the register. Figure 1.58 shows the block
diagram for Real-time port output. Figure 1.59 shows the Real-time control register. Figure 1.60
shows timing in Real-time port output operation.
Data bus
TAiiN
f1 fS f32 fC132
Timer Bj overflow
Timer Ak
overflow
2
Noise
filter
* Timer mode
Timer Ai
j=2, k=4, 0, m=0, 1 when i=0, 1
Timer Ai+1
overflow
Set values for Real-time port used in Timer Ai mode register
Timer Ai mode register (Address 039616 and 039716)
b7 b6 b5 b4 b3 b2 b1 b0
00
00
Data bus
Data bus
Timer Ai interrupt
Data bus
Data bus
Fig. 1.58. Block diagram of Real-time port output
Port
latch
Port
latch
TQ
P30/RTP00
D
RTP0 Real-time
port select bit
TQ
P31/RTP01
D
~~
~~
Port
latch
Port
latch
TQ
P46/RTP70
D
RTP7 Real-time
port select bit
TQ
P47/RTP71
D
Real time port latch
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