
APPENDIX B LIST OF CAUTIONS
User’s Manual U17894EJ9V0UD
903
(4/35)
Chapter
Cl
assi
fi
cati
on
Function
Details of
Function
Cautions
Page
Soft
P140/PCLBUZ0/
INTP6,
P141/PCLBUZ1/
INTP7
To use P140/PCLBUZ0/INTP6 or P141/PCLBUZ1/INTP7 as a general-purpose port,
set bit 7 of clock output select registers 0 and 1 (CKS0, CKS1) to “0”, which is the
same as their default status settings.
p.145
Hard
Port 15
See 2.2.15 AVREF0 for the voltage to be applied to the AVREF0 pin when using port 15
as a digital I/O.
p.149
PM0 to PM8,
PM11 to PM15:
Port mode
registers
Be sure to set bit 7 of PM0, bits 2 to 7 of PM3, bits 2 to 7 of PM11, bits 1 to 7 of
PM12, bits 2 to 7 of PM13, and bits 6 and 7 of PM14 to “1”. And be sure to set bit 0
of PM13 to “0”.
p.151
Set the channel used for A/D conversion to the input mode by using port mode
registers 2 and 15 (PM2, PM15).
p.156
Do not set the pin set by ADPC as digital I/O by analog input channel specification
register (ADS).
p.156
ADPC: A/D port
configuration
register
P20/ANI0 to P27/ANI7 and P150/ANI8 to P157/ANI15 are set as analog inputs in the
order of P157/ANI15, …, P150/ANI8, P27/ANI7, …, P20/ANI0 by the A/D port
configuration register (ADPC). When using P20/ANI0 to P27/ANI7 and P150/ANI8 to
P157/ANI15 as analog inputs, start designing from P157/ANI15.
p.156
Chapter
4
Soft
Port
functions
1-bit
manipulation
instruction for
port register n
(Pn)
When a 1-bit manipulation instruction is executed on a port that provides both input
and output functions, the output latch value of an input port that is not subject to
manipulation may be written in addition to the targeted bit.
Therefore, it is
recommended to rewrite the output latch when switching a port from input mode to
output mode.
p.163
PER1:
Peripheral
enable register 1
When setting the external bus interface, be sure to set EXBEN to 1 first. If EXBEN =
0, writing to a control register of the external bus interface is ignored, and, even if the
register is read, only the default value is read (except for port mode registers 0, 1, 5,
6, 7, 8 (PM0, PM1, PM5, PM6, PM7, PM8) and port registers 0, 1, 5, 6, 7, 8 (P0, P1,
P5, P6, P7, P8)).
p.170
Chapter
5
Soft
External
bus
interface
Number of
instruction
execution clocks
and instruction
wait clocks for
fetch access
The flash memory and external memory are located in consecutive spaces, but start
fetching in the external memory space by using a branch instruction (CALL, BR) in
the flash memory or RAM memory.
p.174
CMC can be written only once after reset release, by an 8-bit memory manipulation
instruction.
p.191
After reset release, set CMC before X1 or XT1 oscillation is started as set by the
clock operation status control register (CSC).
p.191
Be sure to set AMPH to 1 if the X1 clock oscillation frequency exceeds 10 MHz.
p.191
CMC: Clock
operation mode
control register
It is recommended to set the default value (00H) to CMC after reset release, even
when the register is used at the default value, in order to prevent malfunctioning
during a program loop.
p.191
After reset release, set the clock operation mode control register (CMC) before
starting X1 oscillation as set by MSTOP or XT1 oscillation as set by XTSTOP.
p.192
To start X1 oscillation as set by MSTOP, check the oscillation stabilization time of the
X1 clock by using the oscillation stabilization time counter status register (OSTC).
p.192
Chapter
6
Soft
Clock
generator
CSC: Clock
operation status
control register
Do not stop the clock selected for the CPU/peripheral hardware clock (fCLK) with the
OSC register.
p.192