M16C6C Datasheet, PDF (13/94 Pages) Renesas Technology Corp – RENESAS MCU

M16C/6C Group
1. Overview
1.5 Pin Functions
Table 1.6 Pin Functions (1/3)
Signal Name
Power supply
input
Pin Name
VCC1,
VCC2, VSS
I/O Power Supply
Description
Apply 2.7 to 5.5 V to pins VCC1 and VCC2 (VCC1 ≥ VCC2).
I
-
Input 0V to VSS.⁽¹⁾
Analog power
supply input
Reset input
AVCC, AVSS I
RESET
I
VCC1
VCC1
This is the power supply for the A/D converter. Connect the
AVCC pin to VCC1, and connect the AVSS pin to VSS.
Driving this pin low resets the MCU.
CNVSS
CNVSS
I
VCC1
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.
D0 to D7 I/O
A0 to A19
O
VCC2
VCC2
Inputs or outputs data (D0 to D7) while accessing an
external area with a separate bus.
Outputs address bits A0 to A19.
A0/D0 to
A7/D7
I/O
CS0 to CS3 O
Bus control pins
WR
BHE
O
RD
VCC2
VCC2
VCC2
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.
Outputs chip-select signals CS0 to CS3 to specify an
external area.
Outputs WR, BHE, and RD signals.
• 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.
ALE
O
VCC2 Outputs ALE signal to latch address.
HOLD
I
VCC2
The MCU is placed in a hold state while the HOLD pin is
driven low.
HLDA
O
VCC2 In a hold state, HLDA outputs a low-level signal.
RDY
I
VCC2
The MCU bus is placed in a wait state while the RDY pin is
driven low.
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.
Note:
1. VCC means VCC1 except as otherwise noted.
REJ03B0277-0100 Rev.1.00 Jul.15, 2009
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