UPD784907 Datasheet, PDF (27/98 Pages) NEC – 16-BIT SINGLE-CHIP MICROCONTROLLER

µPD784907, 784908
7.2.3 Special function registers (SFRs)
The special function registers are registers with special functions such as mode registers and control registers for
built-in peripheral hardware. The special function registers are mapped onto the 256-byte space between 0FF00H
and 0FFFFH^Note.
Note On execution of the LOCATION 0 instruction. FFF00H to FFFFFH when the LOCATION 0FH instruction
is executed.
Caution Do not access an address in this area where no SFR is allocated, as the µPD784908 may be placed
in the deadlock state. The deadlock state can be cleared only by a reset.
Table 7-1 lists the special function registers (SFRs). The symbols of the table columns are explained below.
• Symbol .................................... Symbol indicating an on-chip SFR. The symbols listed in the table are reserved
words for the NEC assembler (RA78K4). In the C compiler (CC78K4), the
symbols can be used as sfr variables with the #pragma sfr command.
• R/W ......................................... Indicates whether the SFR is read-only, write-only, or read/write.
R/W: Read/write
R: Read-only.
W: Write-only.
• Bit units for manipulation ....... Indicates the maximum number of bits that can be manipulated whenever an SFR
is manipulated. An SFR that supports 16-bit manipulation can be described in
the sfrp operand. For address specification, an even-numbered address must
be specified.
An SFR that can be manipulated in 1-bit units can be described as the operand
of a bit manipulation instruction.
• After reset ............................... Indicates the state of the register when the RESET signal has been input.
Data Sheet U11680EJ2V0DS00
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