Pin Functions - Renesas M16C/64C User Manual

M16C/64C Group
1.6

Pin Functions

Table 1.7 Pin Functions for the 100-Pin Package (1/3)
Signal Name Pin Name
Power supply
input VCC2, VSS
Analog power
AVCC, AVSS
supply input
Reset input
CNVSS
External data bus
width select input
D0 to D7
D8 to D15
A0 to A19
A0/D0 to
A1/D0 to
CS0 to CS3
Bus control pins
WRL / WR
WRH / BHE
Power supply: VCC2 is used to supply power to the external bus associated pins. The dual power supply configuration
allows VCC2 to interface at a different voltage than VCC1.
R01UH0092EJ0110 Rev.1.10
Jul 31, 2012
I/O Power Supply
VCC1,
I
I VCC1
RESET
I VCC1
CNVSS I VCC1
BYTE I VCC1
I/O VCC2
I/O VCC2
O VCC2
I/O VCC2
A7/D7
I/O VCC2
A8/D7
O VCC2
O VCC2
RD
ALE O VCC2
HOLD
I VCC2
HLDA
O VCC2
RDY
I VCC2
Apply 2.7 to 5.5 V to pins VCC1 and VCC2 (VCC1 ≥ VCC2)
-
and 0 V to the VSS pin.
This is the power supply for the A/D and D/A converters.
Connect the AVCC pin to VCC1, and connect the AVSS pin
to VSS.
Driving this pin low resets the MCU.
Input pin to switch processor modes. After a reset, to start
operating in single-chip mode, connect the CNVSS pin to
VSS via a resistor. To start operating in microprocessor
mode, connect the pin to VCC1.
Input pin to select the data bus of the external area. The data
bus is 16 bits when it is low, and 8 bits when it is high. This
pin must be fixed either high or low. Connect the BYTE pin to
VSS in single-chip mode.
Inputs or outputs data (D0 to D7) while accessing an
external area with a separate bus.
Inputs or outputs data (D8 to D15) while accessing an
external area with a 16-bit separate bus.
Outputs address bits A0 to A19.
Inputs or outputs data (D0 to D7) and outputs address bits
(A0 to A7) by timesharing, while accessing an external area
with an 8-bit multiplexed bus.
Inputs or outputs data (D0 to D7) and outputs address bits
(A1 to A8) by timesharing, while accessing an external area
with a 16-bit multiplexed bus.
Outputs chip-select signals CS0 to CS3 to specify an
external area.
Outputs WRL , WRH , ( WR , BHE ), and RD signals. WRL and
WRH can be switched with BHE and WR .
WRL , WRH , and RD selected
•
If the external data bus is 16 bits, data is written to an even
address in an external area when WRL is driven low. Data
is written to an odd address when WRH is driven low. Data
is read when RD is driven low.
WR , BHE , and RD selected
•
Data is written to an external area when WR is driven low.
Data in an external area is read when RD is driven low. An
odd address is accessed when BHE is driven low. Select
WR , BHE , and RD when using an 8-bit external data bus.
Outputs an ALE signal to latch the address.
HOLD input is unavailable. Connect the HOLD pin to VCC2
via a resistor (pull-up).
In a hold state, HLDA outputs a low-level signal.
The MCU bus is placed in a wait state while the RDY pin is
driven low.
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