CHAPTER 3: PRECAUTIONS ON USING THE S5U1C63004P PERIPHERAL CIRCUIT BOARD
S5U1C63004P MANUAL (PERIPHERAL CIRCUIT
EPSON
3
BOARD FOR S1C63454/63455/63458/63466)
CHAPTER
3
P
RECAUTIONS
ON
U
SING
THE
S5U1C63004P
P
ERIPHERAL
C
IRCUIT
B
OARD
Follow the precautions described below to ensure that your S5U1C63004P board is used properly. Note,
however, that some functions described here may not be available with some models. For details, refer to
the technical hardware manual for each model.
3.1 Operation Precautions
(1) Always be sure to power off all connected equipment before connecting or disconnecting the cable.
(2) When supplying an LCD drive power from an external source, make sure that the supply voltage
satisfies the equation below. Note that this applies to the model that is designed to allow supply of the
LCD drive power from an external source. Therefore, you have to set the mask option to choose an
external power supply.
V
SS
< V
C1
< V
C2
< V
C3
< V
C4
< V
C5
≤
V
DD
(= +5 V)
(3) Do not turn the power on and do not load any mask option data while the input ports (K00–K03) are
all set to low level. It may cause a simultaneous key input reset.
3.2 Differences from an Actual IC
The S5U1C63004P emulation board differs in terms of functionality and characteristics from an actual IC,
a fact with requires your attention. If these differences are ignored, there is a possibility that your circuit
will not operate properly on an actual IC even though it might have performed well on the ICE.
(1) Difference in I/O
<Interface voltage>
The interface voltage between the S5U1C63004P board and the target system is fixed at +5 V. There-
fore, if your emulation requires using the same interface voltage as that of an actual IC, add a level
shifter circuit or some other appropriate circuit to the target system to satisfy this requirement.
<Output port drive capability>
The drive capability of each output port on the S5U1C63004P board is somewhat higher than that of
an actual IC. Check the drive capacity of each output terminal on the model by referring to its techni-
cal hardware manual before you design the system and software.
<Protective diode at each port>
The S5U1C63004P board contains V
DD
and V
SS
protective diodes at all I/O ports and the interface
voltage with the target is fixed at +5 V. Therefore, you cannot set the output ports on the
S5U1C63004P board for open-drain output and interface them with a voltage level exceeding V
DD
.
<Pull-up resistance>
The pull-up resistors on the S5U1C63004P board are fixed to a resistance value of about 220 k
Ω
which
is different from that of an actual IC. Consult the technical hardware manual to check the pull-up
resistance of the actual IC.
When turning input terminals high with pull-up resistors, note that there is a difference in the time it
takes to set up the high level. For example, if you configure a key matrix circuit using a combination
of output and input ports, and pull the configuration high with pull-up resistors at the input ports, a
difference may result in a rise time delay.
(2) Difference in current consumption
Current consumption in the S5U1C63004P board greatly differs from that in an actual IC. Check the
LEDs on the S5U1C63004P board to estimate the approximate current consumption of the board. The
following lists the items that greatly affect the amount of current consumption:
