4513 datasheet(53/97 Pages) RENESAS

53 / 97 page

4513/4514 Group

SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

MITSUBISHI MICROCOMPUTERS

(4) Return signal

An external wakeup signal is used to return from the RAM back-up

mode because the oscillation is stopped. Table 21 shows the return

condition for each return source.

(5) Ports P0 and P1 control registers

• Key-on wakeup control register K0

tion. Set the contents of this register through register A with the

TK0A instruction. In addition, the TAK0 instruction can be used to

transfer the contents of register K0 to register A.

• Pull-up control register PU0

transistor. Set the contents of this register through register A with

the TPU0A instruction. In addition, the TAPU0 instruction can be

used to transfer the contents of register PU0 to register A.

Table 21 Return source and return condition

Remarks

Set the port using the key-on wakeup function selected with register K0 to

“H” level before going into the RAM back-up state because the port P0

shares the falling edge detection circuit with port P1.

Select the return level (“L” level or “H” level) with the bit 2 of register I1 ac-

cording to the external state before going into the RAM back-up state.

Select the return level (“L” level or “H” level) with the bit 2 of register I2 ac-

cording to the external state before going into the RAM back-up state.

Return condition

Return by an external falling

edge input (“H”

→“L”).

Return by an external “H” level or

“L” level input.

The EXF0 flag is not set.

Return by an external “H” level or

“L” level input.

The EXF1 flag is not set.

Return source

Ports P0, P1

Port P30/INT0

Port P31/INT1

4513 Datasheet(PDF) 53 Page - Renesas Technology Corp