upd17240 Renesas Electronics Corporation., upd17240 Datasheet - Page 32

• Manufacturer Part Number: upd17240
• Description: 4-bit Single-chip Microcontrollers For Small General-purpose Infrared Remote Control Transmitters
• Manufacturer: Renesas Electronics Corporation.

2.5.2
prohibited from being read or written.
window register.
file addressed by “rf”.
manipulation instructions, can be used. The macro instructions allow the contents of the register file to be manipulated
in bit units.
2.5.3
Subseries User’s Manual (U12795E).
32
SETn:
CLRn:
SKTn:
SKFn:
NOTn:
INITFLG:
INITFLGX: Initializes flag
(1) When manipulating control registers (read-only and unused registers)
The control registers consist of a total of 64 nibbles (64 × 4 bits) of addresses 00H to 3FH of the register file.
Of these, however, only 24 nibbles are actually used. The remaining 40 nibbles are unused registers that are
When the “PEEK WR, rf” instruction is executed, the contents of the register file addressed by “rf” are read to the
When the “POKE rf, WR” instruction is executed, the contents of the window register are written to the register
When using the assembler (RA17K), the macro instructions listed below, which are embedded as flag type symbol
For the configuration of the control register, refer to Figure 12-1 Register File List.
When using the register files, bear in mind the points described below. For details, refer to the µ PD172xx
When manipulating the write-only (W), the read-only (R), and unused control registers by using an assembler
or in-circuit emulator, keep in mind the following points.
• When device operates
• Using assembler
• When an in-circuit emulator (IE-17K or IE-17K-ET) is used (when an instruction is executed for patch
Control registers
Notes on using register files
Nothing changes even if data is written to a read-only register.
If an unused register is read, an undefined value is read; nothing is changed even if data is written to this
register.
An error occurs if an instruction is executed to read data from a write-only register.
An error occurs if an instruction is executed to write data to a read-only register.
An error also occurs if an instruction is executed to read or write an unused address.
processing)
An undefined value is read if a write-only register is read, and an error does not occur.
Nothing changes even if data is written to a read-only register, and an error does not occur.
An undefined value is read if an unused address is read; nothing changes even if data is written to this
address. An error does not occur.
Sets flag to “1”
Sets flag to “0”
Skips if all flags are “1”
Skips if all flags are “0”
Inverts flag
Initializes flag
µ PD17240, 17241, 17242, 17243, 17244, 17245, 17246
Data Sheet U15002EJ1V1DS