PRELIMINARY
Notice:
This
is not
a final
specification.
Some
parametric
limits
are
subject
to change.
4
PROM VERSION OF M37736MHBXXXGP
MITSUBISHI MICROCOMPUTERS
M37736EHBXXXGP
M37736EHBGS
PIN DESCRIPTION
XIN
Clock input
Input
Bus method
select input
XOUT
Clock output
Output
Pin
Name
Input/Output
Functions
Vcc,
Power source
Apply 5 V ± 10% to Vcc and 0 V to Vss.
Vss
CNVss
CNVss input
Input
This pin controls the processor mode. Connect to Vss for the single-chip mode and the memory
expansion mode, and to Vcc for the microprocessor mode.
_____
RESET
Reset input
Input
When “L” level is applied to this pin, the microcomputer enters the reset state.
These are pins of main-clock generating circuit. Connect a ceramic resonator or a quartz-
crystal oscillator between XIN and XOUT. When an external clock is used, the clock source should
be connected to the XIN pin, and the XOUT pin should be left open.
_
E
Enable output
Output
This pin functions as the enable signal output pin which indicates the access status in the internal
bus. In the external bus mode B and the memory expansion mode or the microprocessor mode,
___
this pin output signal RDE.
BYTE
External data
Input
In the memory expansion mode or the microprocessor mode, this pin determines whether the
bus width
external data bus has an 8-bit width or a 16-bit width. The data bus has a 16-bit width when “L”
selection input
signal is input and an 8-bit width when “H” signal is input.
BSEL
Input
In the memory expansion mode or the microprocessor mode, this pin determines the external bus
mode. The bus mode becomes the external bus mode A when “H” signal is input, and the external
bus mode B when “L” signal is input.
AVcc,
Analog power
Power source input pin for the A-D converter. Externally connect AVcc to Vcc and AVss to Vss.
AVss
source input
VREF
Reference
Input
This is reference voltage input pin for the A-D converter.
voltage input
P00 – P07
I/O port P0
I/O
In the single-chip mode, port P0 becomes an 8-bit I/O port. An I/O direction register is available so
that each pin can be programmed for input or output. These ports are in the input mode when
reset.
In the memory expansion mode or the microprocessor mode, these pins output address (A0 – A7)
___
____
at the external bus mode A, and these pins output signals CS0 – CS4 and RSMP, and addresses
(A16, A17) at the external bus mode B.
P10 – P17
I/O port P1
I/O
In the single-chip mode, these pins have the same functions as port P0. When the BYTE pin is set
to “L” in the memory expansion mode or the microprocessor mode and external data bus has a
16-bit width, high-order data (D8 – D15) is input/output or an address (A8 – A15) is output. When
the BYTE pin is “H” and an external data bus has an 8-bit width, only address (A8 – A15) is output.
P20 – P27
I/O port P2
I/O
In the single-chip mode, these pins have the same functions as port P0. In the memory expansion
mode or the microprocessor mode, low-order data (D0 – D7) is input/output or an address is
output. When using the external bus mode A, the address is A16 – A23. When using the external
bus mode B, the address is A0 – A7.
P30 – P33
I/O port P3
I/O
In the single-chip mode, these pins have the same function as port P0. In the memory expansion
__
___
____
mode or the microprocessor mode, R/W, BHE, ALE, and HLDA signals are output at the external
___
____
bus mode A, and WEL, WEH, ALE, and HLDA signals are output at the external bus mode B.
P40 – P47
I/O port P4
I/O
In the single-chip mode, these pins have the same functions as port P0. In the memory expansion
____
___
mode or the microprocessor mode, P40, P41 and P42 become HOLD and RDY input pins, and a
clock
φ1 output pin, respectively. Functions of the other pins are the same as in the single-chip
mode. However, in the memory expansion mode, P42 can be selected as an I/O port.
P50 – P57
I/O port P5
I/O
In addition to having the same functions as port P0 in the single-chip mode, these pins also
function as I/O pins for timers A0 to A3.
P60 – P67
I/O port P6
I/O
In addition to having the same functions as port P0 in the single-chip mode, these pins also
___
function as I/O pins for timer A4, input pins for external interrupt input (INT0 – INT2) and input pins
for timers B0 to B2. P67 also functions as sub-clock
φSUB output pin.
P70 – P77
I/O port P7
I/O
In addition to having the same functions as port P0 in the single-chip mode, these pins function as
input pins for A-D converter. Additionally, P76 and P77 have the function as the output pin (XCOUT)
and the input pin (XCIN) of the sub-clock (32 kHz) oscillation circuit, respectively. When P76 and
P77 are used as the XCOUT and XCIN pins, connect a resonator or an oscillator between the both.
P80 – P87
I/O port P8
I/O
In addition to having the same functions as port P0 in the single-chip mode, these pins also
function as I/O pins for UART 0 and UART 1.
P90 – P97 Output port P9
Output
Port P9 is an 8-bit I/O port. These ports are floating when reset. When writting to the port latch,
these ports become the output mode. P90 – P93 also function as I/O port for UART 2.
P100 – P107 I/O port P10
I/O
In addition to having the same functions as port P0 in the single-chip mode, P104 – P107 also
__
function as input pins for key input interrupt input (KI0 – KI3).
Output
These pins should be left open.
EVL0, EVL1
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