CHAPTER 8 8-BIT TIMER H1
User’s Manual U17446EJ3V1UD
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(2) Port mode register 4 (PM4)
This register sets port 4 input/output in 1-bit units.
When using the P42/TOH1 pin for timer output, clear PM42 and the output latch of P42 to 0.
PM4 can be set by a 1-bit or 8-bit memory manipulation instruction.
Generation of reset signal sets this register to FFH.
Figure 8-5. Format of Port Mode Register 4 (PM4)
Address: FF24H After reset: FFH R/W
Symbol
7 6 5 4 3 2 1 0
PM4
PM47 PM46 PM45 PM44 PM43 PM42 PM41 PM40
PM4n
P4n pin I/O mode selection (n = 0 to 7)
0
Output mode (output buffer on)
1
Input mode (output buffer off)