M37517F8HP Datasheet, PDF (7/98 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

7517 Group
I/O PORTS
The I/O ports have direction registers which determine the input/
output direction of each individual pin. Each bit in a direction reg-
ister corresponds to one pin, and each pin can be set to be input
port or output port.
When “0” is written to the bit corresponding to a pin, that pin be-
comes an input pin. When “1” is written to that bit, that pin
becomes an output pin.
If data is read from a pin which is set to output, the value of the
port output latch is read, not the value of the pin itself. Pins set to
input are floating. If a pin set to input is written to, only the port
output latch is written to and the pin remains floating.
Table 2 I/O port function
Pin
Name
P00/SIN2
P01/SOUT2
P02/SCLK2
P03/SRDY2
Port P0
P04/AN8–P07/AN11
P10–P17
Port P1
P20/XCOUT
P21/XCIN
Port P2
P22/SDA1
P23/SCL1
P24/SDA2/RxD
P25/SCL2/TxD
P26/SCLK
P27/CNTR0/
SRDY1
P30/AN0–
P35/AN5
P40/CNTR1
P41/INT0
P42/INT1
P43/INT2/SCMP2
Port P3
Port P4
P44/INT3/PWM
P45/DFETCNT
Input/Output
Input/output,
individual
bits
I/O Structure
CMOS compatible
input level
CMOS 3-state output
CMOS compatible
input level
CMOS/SMBUS input
level (when selecting
I²C-BUS interface
function)
N-channel open-drain
output
CMOS compatible
input level
CMOS/SMBUS input
level (when selecting
I²C-BUS interface
function)
CMOS 3-state output
N-channel open-drain
output (when
selecting I²C-BUS
interface function)
CMOS compatible
input level
CMOS 3-state output
Non-Port Function
Serial I/O2 function I/O
A/D conversion input
Sub-clock generating
circuit
I²C-BUS interface func-
tion I/O
Related SFRs
Serial I/O2 control
register
A/D control register, MISRG2
CPU mode register
MISRG2
I²C control register
Ref.No.
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
I²C-BUS interface func- ^{I2C control register}
(11)
tion I/O
Serial I/O1 control
(12)
register
Serial I/O1 function I/O
Serial I/O1 function I/O Serial I/O1 control
(13)
register
Serial I/O1 function I/O Serial I/O1 control
(14)
Timer X function I/O
register
Timer XY mode register
A/D conversion input
A/D control register
(5)
MISRG2
Timer Y function I/O
Timer XY mode register (15)
External interrupt input Interrupt edge selection (16)
register
External interrupt input Interrupt edge selection (17)
SCMP2 output
register
Serial I/O2 control
register
External interrupt input Interrupt edge selection (18)
PWM output
register
PWM control register
Over current detector _{Short current detect}
(19)
output
control register
Over current detect
control register
Wake up current detect
control register
Rev.1.01 Aug 02, 2004 page 7 of 96