Motorola MCF5281, MCF5282 user manual Bus and Control Signals, ColdFire Bus Signal Summary

Chapter 13

External Interface Module (EIM)

This chapter describes data-transfer operations, error conditions, and reset operations. Chapter 15, “Synchronous DRAM Controller Module,” describes DRAM cycles.

NOTE:

Unless otherwise noted, in this chapter, “clock” refers to the

CLKOUT used for the bus.

13.1 Features

The following list summarizes bus operation features:

•Up to 24 bits of address and 32 bits of data

•Access 8-, 16-, and 32-bit data port sizes

•Generates byte, word, longword, and line-size transfers

•Burst and burst-inhibited transfer support

•Optional internal termination for external bus cycles

13.2 Bus and Control Signals

Table 13-1summarizes MCF5282 bus signals described in Chapter 14, “Signal Descriptions.”

Table 13-1. ColdFire Bus Signal Summary

Signal Name					Description	I/O	CLKOUT Edge
	A[23:0]				Address bus	O	Rising
			1		Byte selects	O	Falling
		BS
					Chip selects	O	Falling
	CS[6:0] 1
	D[31:0]				Data bus	I/O	Rising
				1	Output enable	O	Falling
		OE
					Read/write	O	Rising
		R/W
	SIZ[1:0]				Transfer size	O	Rising

MOTOROLA Chapter 13. External Interface Module (EIM) 13-1