134
CHAPTER 6 PORT FUNCTIONS
Control register
6.2 Port Configuration
A port consists of the following hardware:
Table 6-3. Port Configuration
Item
Configuration
Port mode register (PMm: m = 0 to 3, 5 to 10, 12, 13)
Pull-up resistor option register (PUOH, PUOL)
Memory expansion mode register (MM)
Note
Key return mode register (KRM)
Port
Total: 69 ports (2 inputs, 67 inputs/outputs)
• Mask ROM version
Pull-up resistor
Total: 67 (software specifiable: 63, mask option: 4)
• PROM version Total: 63
Note
MM specifies port 4 input/output.
6.2.1 Port 0
Port 0 is an 8-bit input/output port with output latch. P01 to P06 pins can specify the input mode/output mode in
1-bit units with the port mode register 0 (PM0). P00 and P07 pins are input-only ports. When P01 to P06 pins are
used as input ports, an on-chip pull-up resistor can be used to them in 6-bit units with a pull-up resistor option register
L (PUOL).
Alternate functions include external interrupt request input, external count clock input to the timer and crystal
connection for subsystem clock oscillation.
RESET input sets port 0 to input mode.
Figures 6-2 and 6-3 show block diagrams of port 0.
Caution Because port 0 also serves for external interrupt request input, when the port function output
mode is specified and the output level is changed, the interrupt request flag is set. Thus, when
the output mode is used, set the interrupt mask flag to 1.
Summary of Contents for PD78052
Page 2: ...2 MEMO ...
Page 8: ...8 MEMO ...
Page 16: ...16 MEMO ...
Page 36: ...36 MEMO ...
Page 158: ...158 MEMO ...
Page 174: ...174 MEMO ...
Page 240: ...240 MEMO ...
Page 260: ...260 MEMO ...
Page 340: ...340 MEMO ...
Page 392: ...392 MEMO ...
Page 438: ...438 MEMO ...
Page 482: ...482 CHAPTER 20 REAL TIME OUTPUT PORT MEMO ...
Page 510: ...510 MEMO ...
Page 524: ...524 MEMO ...
Page 560: ...560 MEMO ...
Page 576: ...576 MEMO ...
Page 598: ...598 MEMO ...
Page 602: ...602 MEMO ...