ICS Advent DIO24-P, Руководство по эксплуатации продукта

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Chapter 3: Programming
Manual Number: 00431-024-14 Page 3-3
Mode 1
This functional configuration provides a means for transferring I/O data to or from a specified port
in conjunction with strobes or “handshaking” signals. In Mode 1, Port A and Port B use the lines
on Port C to generate or accept these “handshaking” signals.
Mode 1 Basic Functional Definitions
• Two Groups (Group A and Group B)
• Each group contains one 8-bit data port and one 4-bit control/data port
• The 8-bit data port can be either input or output. Both inputs and outputs are latched
• The 4-bit port is used for control and status of the 8-bit data port
Mode 2
This functional configuration provides a means for communicating with a peripheral device or
structure on a single 8-bit bus for both transmitting and receiving data (bidirectional bus I/O).
“Handshaking” signals are provided to maintain proper bus flow discipline in a similar manner to
MODE 1. Interrupt generation and enable/disable functions are also available.
Mode 2 Basic Functional Definitions
• Used in Group A only
• One 8-bit, bidirectional bus port (Port A) and a 5-bit control port (Port C)
• Both inputs and outputs are latched
• The 5-bit control port (Port C) is used for control and status for the 8-bit, bi-directional bus port
(Port A)
Bit Set/Reset
Any of the eight bits of Port C can be Set or Reset using a single OUTput instruction. This feature
reduces software requirements in control-based applications.
When Port C is being used as status/control for Port A or B, these bits can be set or reset by using
the Bit Set/Reset operation just as if they were data output ports.
Bit 7 controls the Bit Set/Reset function. When bit 7=1 the port is a control port. When set to 0 the
Bit Set/Reset function is used.
Bit Set/Reset Format