Tamagawa

Table of Contents

• Introduction
• Features Supported
• Features Not Supported
• SysConfig Features
• ICSS PRU Resource Usage
• Tamagawa Design
• Example
• API

Introduction

The Tamagawa receiver firmware running on PRU-ICSS provides a defined well interface to execute the Tamagawa protocol. The Tamagawa diagnostic application interacts with the Tamagawa receiver firmware interface.

Note

Tamagawa firmware and examples are based on 3 Channel Peripheral interface from PRU-ICSSM.

Features Supported

• Supports full-absolute SmartAbs & SmartInc encoders compatible with Smartceiver AU5561N1
• Channel selection
• Baud rate selection
• Supports all Data Readout, Reset and EEPROM commands
• 2.5 Mbps and 5 Mbps encoder support

  Note

  Receive (Rx) is oversampled at 8x of send(Tx). Therefore, the encoder interface frequency "f" should such that Tx source clock value is divisible by "f" and Rx source clock value is divisible by "(8*f)".

• Possible interface speeds with different source clock combinations.

  Clock Source	Interface Speed
  PRU UART Clock (160 MHz)	2.5MHz, 5MHz
  PRU Core Clock (200 MHz)	2.5MHz, 5MHz

Features Not Supported

In general, peripherals or features not mentioned as part of "Features Supported" section are not supported, including the below

• Other baud rates.

SysConfig Features

Note

It is strongly recommend to use SysConfig where it is available instead of using direct SW API calls. This will help simplify the SW application and also catch common mistakes early in the development cycle.

SysConfig can be used to configure things mentioned below:

• Selecting the ICSSM PRU slice (Tested on ICSSM-PRU0)
• Configuring PINMUX and GPIO
• Selecting the ICSSG instance
• Selecting the ICSSG PRU slice (Tested on ICSSG0-PRU1)
• Configuring PINMUX, GPIO and ICSS clock to 200MHz
• Enabling SA Mux mode
• Channel selection
• Baud rate selection
• Selecting RX and TX source clock

ICSS PRU Resource Usage

Configuration	PRU Core	Memory Usage	IEP Usage	Other Peripheral Usage	Description
Single Channel Configuration	PRUx	DMEM: 220 Bytes IMEM: 1.8 KB	IEP0: CMP0 and CMP3	INTC Signal No. 18 is used to trigger a R5 interrupt	IEP, CMP events and INTC signal are used only in periodic continuous mode

Note

For pin usage, see Pin Multiplexing section.

Tamagawa Design

Tamagawa Protocol Design explains the design in detail.

Example

• Tamagawa Diagnostic

API

APIs for Tamagawa Encoder