17 Parallel Interface (PIO)
S1C17F13 TeChniCal Manual
Seiko epson Corporation
17-1
(Rev. 1.0)
Parallel Interface (PIO)
17
Overview
17.1
PIO is an 8-bit parallel interface that allows connection of an SRAM type device. The features of PIO are listed be-
low.
• 8-bit data bus
• 8-bit address bus
• Bus control output signals: read, write, and chip enable
• Provides GPIO mode to use the address bus pins as general-purpose output ports and the data bus pins as general-
purpose input ports.
• Provides PIO pins with pull-up control.
Figure 17.1.1 shows the PIO configuration.
PIO
CLKSRC[1:0]
CLKDIV[1:0]
Access control
circuit
Address
PADDR[7:0]
Write data
PWDATA[7:0]
Read data
PRDATA[7:0]
Clock generator
DBRUN
MODEN
CLK_PIO
PUL
GPIOMD
SFTRST
WBUSY
RBUSY
RACC
#PIOCE
#PIORD
#PIOWR
PIOA[7:0]
PIOD[7:0]
Inter
nal data
bu
s
I/O cell
1.1 PIO Configuration
Figure 17.
Input/Output Pins and External Connections
17.2
List of Input/Output Pins
17.2.1
Table 17.2.1.1 lists the PIO pins.
2.1.1 List of PIO Pins
Table 17.
Pin name
I/O
*
Initial status
*
Function
PIOA[7:0]
O
O (Low)
PIO address output
PIOD[7:0]
I/O
I (Hi-Z)
PIO data input/output
#PIOCE
O
O (High)
PIO chip enable signal output
#PIORD
O
O (High)
PIO read signal output
#PIOWR
O
O (High)
PIO write signal output
*
Indicates the status when the pin is configured for PIO.
If the port is shared with the PIO pin and other functions, the PIO input/output function must be assigned to the
port before activating PIO. For more information, refer to the “I/O Ports” chapter.