FUJITSU Semiconductor Controller MB89950/950A - Manual (Page 91)

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CHAPTER 4 I/O PORTS
4.3 Port 1
Port 1 is N-ch open-drain I/O port that also serves as LCD segment driver outputs. Port
1 pins can be switched between LCD segment driver output and port operation by mask
option. This section principally describes the port functions when operating as N-ch
open-drain I/O port.
The section describes the port structure and pins, the pin block diagram, and the port
register for port 1.
■ Structure of port 1
Port 1 consists of the following two components:
• N-ch open-drain I/O pins/LCD segment driver output pins (P10/SEG28 to P17/SEG35)
• Port 1 data register (PDR1)
■ Port 1 pins
Port 1 consists of eight N-ch open-drain I/O. When pins are used by the peripheral, they cannot be used as
N-ch open-drain I/O.
Table 4.3-1 "Port 1 pins" lists the port 1 pins.
See Section 1.7 "I/O Pins and Pin Functions" for a description of the circuit type.
Table 4.3-1 Port 1 pins
Port Pin name Function Shared peripheral
I/O type
Circuit
type
Input Output
Port 1
P10/SEG28 P10 N-ch open-drain I/O SEG28 LCD segment driver output
CMOS
Segment / N-ch
open-drain
D
P11/SEG29 P11 N-ch open-drain I/O SEG29 LCD segment driver output
P12/SEG30 P12 N-ch open-drain I/O SEG30 LCD segment driver output
P13/SEG31 P13 N-ch open-drain I/O SEG31 LCD segment driver output
P14/SEG32 P14 N-ch open-drain I/O SEG32 LCD segment driver output
P15/SEG33 P15 N-ch open-drain I/O SEG33 LCD segment driver output
P16/SEG34 P16 N-ch open-drain I/O SEG34 LCD segment driver output
P17/SEG35 P17 N-ch open-drain I/O SEG35 LCD segment driver output