TMP86FP24 Datasheet, PDF (50/217 Pages) Toshiba Semiconductor – 8 Bit Microcontroller

TMP86FP24
2.2 I/O Ports
The TMP86FP24 has 8 parallel input/output ports (54 pins) as follows.
Port P0
Port P1
Port P2
Port P3
Port P4
Port P5
Port P6
Port P9
Primary Function
8-bit I/O port
6-bit I/O port
4-bit I/O port
8-bit I/O port
8-bit I/O port
4-bit I/O port
8-bit I/O port
8-bit I/O port
Secondary Functions
External interrupt input, serial interface input/output, UART input/output and
timer/counter input .
External interrupt input, serial interface input/output and timer/counter
input/output.
Low-frequency resonator connections, external interrupt input, STOP mode
release signal input.
Segment output and STOP mode release signal input.
Divider output and timer/counter output.
Analog input and STOP mode release signal input.
Segment output.
Each output port contains a latch, which holds the output data. All input ports do not have
latches, so the external input data should be externally held until the input data is read from
outside or reading should be performed several times before processing. Figure 2.2.1 shows
input/output timing examples.
External data is read from an I/O port in the S1 state of the read cycle during execution of the
read instruction. This timing cannot be recognized from outside, so that transient input such as
chattering must be processed by the program.
Output data changes in the S2 state of the write cycle during execution of the instruction
which writes to an I/O port.
Instruction execution cycle
Input strobe
Data input
Fetch cycle
Fetch cycle
Read cycle
S0 S1 S2 S3 S0 S1 S2 S3 S0 S1 S2 S3
Ex: LD A, (x)
(a) Input timing
Instruction execution cycle
Fetch cycle
Fetch cycle
Read cycle
S0 S1 S2 S3 S0 S1 S2 S3 S0 S1 S2 S3
Ex: LD (x), A
Output strobe
Data output
Old
New
(b) Output timing
Note: The positions of the read and write cycles may vary, depending on the instruction.
Figure 2.2.1 Input/Output Timing (Example)
86FP24-48
2007-08-24