USB Mass-Storage Implementation on an Embedded System (D0113)

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USB Mass-Storage Implementationon an Embedded
System(D0113)
Final Presentation 20/4/2004

• Supervisor
• Dimitry Sokolik
• Performed by
• Yoav Gershoni
• Shachar Faigenblat

HSDS LAB Technion - Winter 2003
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Project overview

• The project provides generic means to read files
  from a FAT32 formatted USB-Flash-Disk.
• Stage A
• PC implementation all the logic and the
  protocol layers will be implemented on the PC.
• Stage B
• Full on board implementation (hardware
  application).

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Block Diagram
Stage A
PIC Evaluation Board
Flat Cable 23 bits
Parallel Connection
USB BUS
USB Host Controller
Pic Microprocessor
RS 232
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Block Diagram
Stage B
PIC Evaluation Board
Flat Cable 23 bits
Parallel Connection
USB BUS
USB Host Controller
Pic Microprocessor
The application will be implemented on the PIC
itself
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Project Specification

• Components
• PIC 18F452 evaluation board.
• Philips ISP1362 USB Host Controller.
• Power supply
• 9v from external PS converted to 5v and 3.3v.
• 5v for the evaluation board, PIC and USB bus.
• 3.3v for the host controller.
• Interfaces
• USB bus between Flash Disk and Host Controller.
• parallel bus between PIC ports and Host
  Controller.
• RS-232 bus between the PC and the PIC board.

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Project Specification Cont

• Connectors
• Type A USB connector.
• D-Type-9 connector. (for RS-232 already exists
  on the evaluation board and on PC).

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Project background

• Stand alone device.
• Stage A Application on the PC.
• Microprocessor instead of FPGA to control the USB
  HC.
• Future implementations - MP3 decoder.

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Software Architecture
Logical File System Layer FAT16/FAT32
Command Set Protocol Using SCSI Primary Command
Set
USB Mass-Storage Class Using Bulk-Only Transport
protocol
Host Controller Driver
PC PIC Communication
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Software Development Tools

• PIC
• MCC18 compiler on MPLAB IDE.
• PC
• Code in C, with Visual Studio compiler.
• USB protocol
• USB Inspector.

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Project Status

• PC-PIC Communication.
• HC Board.
• USB Protocol Analysis.

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PIC-HC Connection

• HC has 16 I/O bits.
• Command or Data Control bit (A0).
• Method
• Send Command. (A01)
• Send/Receive Data. (A00)

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Writing 16/32 bits to HC
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PC-PIC Protocol

• Over RS232.115200bps, 8 bits, no parity, 1 stop
  bit.
• Transactions has Command and Data.

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Software Design

• PC-PIC Connection Protocol Design.
• Learn RS232 Communication on PC.
• RS232 on PIC using Lee Ehud LIB.
• Implementation of PC-PIC Protocol on PC and PIC.

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HC Board Design

• Connection To PIC (ports assignment)
• Buffers to Convert Logical Levels 5v lt-gt 3.3v
• Power Supply 5v, 3.3v
• USB Connector with Over Current Sense.
• Good Link Led.
• Manual Reset.
• Clock.

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USB Protocol Analysis

• SCSI Commands Understanding.
• SCSI Commands Specifications Drafts not Final.

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The End
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PC-PIC Protocol
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(No Transcript)
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Ports Table