6 I/O PORTS (PPORT)
S1C17M20/M21/M22/M23/M24/M25
Seiko Epson Corporation
6-1
TECHNICAL MANUAL (Rev. 1.0)
6 I/O Ports (PPORT)
6.1 Overview
PPORT controls the I/O ports. The main features are outlined below.
• Allows port-by-port function configurations.
- Each port can be configured with or without a pull-up or pull-down resistor.
- Each port can be configured with or without a chattering filter.
- Allows selection of the function (general-purpose I/O port (GPIO) function, up to four peripheral I/O func-
tions) to be assigned to each port.
• Ports, except for those shared with debug pins, are initially placed into Hi-Z state.
(No current passes through the pin during this Hi-Z state.)
Note: ‘x’, which is used in the port names Pxy, register names, and bit names, refers to a port group (x
= 0, 1, 2, ··· , d) and ‘y’ refers to a port number (y = 0, 1, 2, ··· , 7).
Figure 6.1.1 shows the configuration of PPORT.
Table 6.1.1 Port Configuration of S1C17M20/M21/M22/M23/M24/M25
Item
S1C17M20/M23
S1C17M21/M24
S1C17M22/M25
24-pin package
32-pin package
Port groups included P0 P0[3:0] (4)
*
1,
*
2
P0[3:0] (4)
*
1,
*
2
P0[3:0] (4)
*
1,
*
2
P0[7:0] (8)
*
1,
*
2
P1 P1[5:2] (4)
*
1,
*
2
P1[5:0] (6)
*
1,
*
2
P1[5:0] (6)
*
1,
*
2
P1[7:0] (8)
*
1,
*
2
P2 P2[7:4] (4)
*
1,
*
2
P2[7:2] (6)
*
1,
*
2
P2[7:2] (6)
*
1,
*
2
P2[7:0] (8)
*
1,
*
2
P3 P3[2:0] (3)
*
1,
*
2
P3[2:0] (3)
*
1,
*
2
P3[2:0] (3)
*
1,
*
2
P3[7:0] (8)
*
1,
*
2
P4 – (0)
– (0)
– (0)
P4[2:0] (3)
*
1,
*
2
Pd Pd[2:0] (3)
*
1
(Pd2: output only)
Pd[4:0] (5)
*
1
(Pd2: output only)
Pd[4:0] (5)
*
1
(Pd2: output only)
Pd[4:0] (5)
*
1
(Pd2: output only)
Total number of ports
Input/output port: 17
Output port:
1
Input/output port: 23
Output port:
1
Input/output port: 23
Output port:
1
Input/output port: 39
Output port:
1
Ports for debug function
Pd[2:0]
Key-entry reset function
Supported (P0[3:0])
*
1 Ports with general-purpose I/O function (GPIO)
*
2 Ports with interrupt function