Chapter 15, Ssi port, Introduction – Cirrus Logic EP73xx User Manual
Page 119: Features, Ssi port register list, Programming example, Chapter 15. ssi port, Table 15-1: ssi port registers -1, Chapter 15 15 ssi port introduction, Ssi port register list programming example
EP7309/11/12 User’s Manual - DS508UM4
15-1
Copyright Cirrus Logic, Inc. 2003
1515
15
Chapter 15
15
SSI Port
Introduction
The EP73xx provides two synchronous serial channels for use with audio devices,
telephony CODECs, and other devices using SPI or Microwire like communications
formats. The first of the two channels supports standard SPI and Microwire formats
for interfacing with low-bandwidth devices and is always associated with the SSI1
unit. The SSI1 interface is most commonly used to communicate with an A/D
convertor for digitizing pen input from a touch screen.
Features
• Dedicated general purpose SPI/Microwire1-compatible master mode
interface (SSI1)
• Selectable positive or negative edge clocking
• Compatible with many low speed ADCs, DACs, and other
peripherals
• 128 kHz max. clock with on-chip PLL (156.8 kHz at a CPU speed of
90 MHz)
• Compatible with external 13 MHz and PLL clock inputs
SSI Port Register List
Programming Example
;*****************************************************************************
; SSI Port 1 sending transmitting a request for data on the Maxim 148 ADC.
; Process requires sending config packet, receive data (byte to discard) send
; another byte, receive byte (real data) send another last byte, receive byte (real data).
; Total packet length is 24 bits. Extended mode off. ADCCON bit SYSCON3 is cleared.
;*****************************************************************************
Table 15-1: SSI Port Registers
Address
Name
Type
Size
Description
Page
0x8000.0500
SYNCIO
R/W
32
SSI ADC Interface Data
Register