Chapter 22

Queued Serial Peripheral Interface

(QSPI) Module

This chapter describes the queued serial peripheral interface (QSPI) module. Following a feature set overview is a description of operation including details of the QSPI’s internal RAM organization. The chapter concludes with the programming model and a timing diagram.

22.1 Overview

The queued serial peripheral interface module provides a serial peripheral interface with queued transfer capability. It allows users to queue up to 16 transfers at once, eliminating CPU intervention between transfers. Transfer RAM in the QSPI is indirectly accessible using address and data registers.

22.2 Features

Programmable queue to support up to 16 transfers without user intervention

Supports transfer sizes of 8 to 16 bits in 1-bit increments

Four peripheral chip-select lines for control of up to 15 devices

Baud rates from 129.4 Kbps to 16.67 Mbps at 66 MHz

Programmable delays before and after transfers

Programmable QSPI clock phase and polarity

Supports wraparound mode for continuous transfers

22.3 Module Description

The QSPI module communicates with the integrated ColdFire CPU using internal memory mapped registers starting at IPSBAR + 0x340. See Section 22.5, “Programming Model.” A block diagram of the QSPI module is shown in Figure 22-1.

MOTOROLA

Chapter 22. Queued Serial Peripheral Interface (QSPI) Module

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Motorola MCF5281, MCF5282 user manual Chapter Queued Serial Peripheral Interface Qspi Module, Module Description