NEC UPD703116 User Manual page 701

(b) Port DH mode control register (PMCDH)
This register can be read/written in 8-bit or 1-bit units.
7 6
PMCDH PMCDH7 PMCDH6
Note 00H: Single-chip mode 0
FFH: Single-chip mode 1, ROMless mode 0 or 1
Bit position Bit name
7 to 0 PMCDHn
(n = 7 to 0)
CHAPTER 14 PORT FUNCTIONS
5 4 3
PMCDH5 PMCDH4 PMCDH3
Specifies operation mode of PDHn pin.
0: I/O port mode
1: A23 to A16 output mode
User's Manual U14492EJ5V0UD
2 1 0
PMCDH2 PMCDH1 PMCDH0
Function
Note
Address Initial value
FFFFF046H 00H/FFH
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