4501 datasheet(119/212 Pages) RENESAS

119 / 212 page

2.1 I/O pins

2-2

Rev.2.01

Feb 07, 2005

4501 Group

APPLICATION

REJ09B0192-0201

2.1 I/O pins

The 4501 Group has the fourteen I/O pins. (Port P12 is also used as CNTR I/O pin, Port P13 is also used

as INT input pin, Port P2 is also used as analog input pins AIN0 and AIN1, Port D2 is also used as Port C,

and Port D3 is also used as Port K, respectively).

This section describes each port I/O function, related registers, application example using each port function

and notes.

2.1.1 I/O ports

(1)

Port P0

Port P0 is a 4-bit I/O port.

Port P0 has the key-on wakeup function which turns ON/OFF with register K0 and pull-up transistor

which turns ON/OFF with register PU0.

s Input/output of port P0

q Data input to port P0

Set the output latch of specified port P0i (i=0 to 3) to “1” with the OP0A instruction. If the output

latch is set to “0,” “L” level is input.

The state of port P0 is transferred to register A when the IAP0 instruction is executed.

q Data output from port P0

The contents of register A is output to port P0 with the OP0A instruction.

The output structure is an N-channel open-drain.

(2)

Port P1

Port P1 is a 4-bit I/O port.

Port P1 has the key-on wakeup function which turns ON/OFF with register K1 and pull-up transistor

which turns ON/OFF with register PU1.

s Input/output of port P1

q Data input to port P1

Set the output latch of specified port P1i (i=0 to 3) to “1” with the OP1A instruction. If the output

latch is set to “0,” “L” level is input.

The state of port P1 is transferred to register A when the IAP1 instruction is executed.

q Data output from port P1

The contents of register A is output to port P1 with the OP1A instruction.

The output structure is an N-channel open-drain.

Note: Port P12 is also used as CNTR. Accordingly, when it is used as port P12, set “0” to the

timer control register W60.

4501 Datasheet(PDF) 119 Page - Renesas Technology Corp

4501 Datasheet(HTML) 119 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL