Texas Instruments TUSB5052 User manual

  
  

February 2004 MSDS Bus Solutions
User’s Guide
SLLU021A

IMPORTANT NOTICE
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Copyright 2004, Texas Instruments Incorporated

Notational Conventions
iii
Preface

About This Manual
This user’s guide contains pertinent information about the bootcode process
of the TUSB5052.
How to Use This Manual
This document contains the following chapters:
-Chapter 1—Introduction
-Chapter 2—TUSB5052 USB Firmware Flow
-Chapter 3—Function
-Chapter 4—Bootcode Defaults
-Chapter 5—Header Format and Vendor USB Request
-Chapter 6—Programming Considerations and Bootcode File List
Notational Conventions
This document uses the following conventions.
-Program listings, program examples, and interactive displays are shown
in a special typeface similar to a typewriter’s. Examples use a bold
version of the special typeface for emphasis; interactive displays use a
bold version of the special typeface to distinguish commands that you
enter from items that the system displays (such as prompts, command
output, error messages, etc.).
Here is a sample program listing:
0011 0005 0001 .field 1, 2
0012 0005 0003 .field 3, 4
0013 0005 0006 .field 6, 3
0014 0006 .even
Here is an example of a system prompt and a command that you might
enter:
C: csr −a /user/ti/simuboard/utilities

FCC Warning
iv
-In syntax descriptions, the instruction, command, or directive is in a bold
typeface font and parameters are in an italic typeface. Portions of a syntax
that are in bold should be entered as shown; portions of a syntax that are
in italics describe the type of information that should be entered. Here is
an example of a directive syntax:
.asect ”section name”, address
.asect is the directive. This directive has two parameters, indicated by sec-
tion name and address. When you use .asect, the first parameter must be
an actual section name, enclosed in double quotes; the second parameter
must be an address.
-Square brackets ( [and ]) identify an optional parameter. If you use an
optional parameter, you specify the information within the brackets; you
don’t enter the brackets themselves. Here’s an example of an instruction
that has an optional parameter:
LALK 16-bit constant [, shift]
The LALK instruction has two parameters. The first parameter,16-bit con-
stant, is required. The second parameter, shift, is optional. As this syntax
shows, if you use the optional second parameter, you must precede it with
a comma.
Square brackets are also used as part of the pathname specification for
VMS pathnames; in this case, the brackets are actually part of the path-
name (they are not optional).
-Braces ( { and } ) indicate a list. The symbol |(read as or) separates items
within the list. Here’s an example of a list:
{ * | *+ | *− }
This provides three choices: *, *+, or *−.
Unless the list is enclosed in square brackets, you must choose one item
from the list.
-Some directives can have a varying number of parameters. For example,
the .byte directive can have up to 100 parameters. The syntax for this di-
rective is:
.byte value1[, ... , valuen]
This syntax shows that .byte must have at least one value parameter, but
you have the option of supplying additional value parameters, separated
by commas.
FCC Warning
This equipment is intended for use in a laboratory test environment only. It gen-
erates, uses, and can radiate radio frequency energy and has not been tested
for compliance with the limits of computing devices pursuant to subpart J of
part 15 of FCC rules, which are designed to provide reasonable protection
against radio frequency interference. Operation of this equipment in other en-
vironments may cause interference with radio communications, in which case
the user at his own expense will be required to take whatever measures may
be required to correct this interference.

Contents
v

1 Introduction 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Bootcode Main Program 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Interrupt Service Routine 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Control (Setup) Endpoint Handler 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Input Endpoint 0 Interrupt Handler 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5 Output Endpoint 0 Handler 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.6 Output Endpoint 1 Handler 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 TUSB5052 USB Firmware Flow 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Control Write Transfer With Data 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Control Write Without Data 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Control Read Transfer 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Function 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Bootcode Functional Module List 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.1 Bootcode.c File 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.2 I2C.c File 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.3 Header.c File 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Bootcode Defaults 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Default Hub Settings 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Default Bootcode Settings 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 Header Format and Vendor USB Request 5-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1 Header Format 5-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.1 Product Signature 5-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.2 Descriptor 5-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.3 Descriptor Prefix 5-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.4 Descriptor Content 5-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2 Examples 5-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.1 USB Info Basic Descriptor 5-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Built-In Vendor-Specific USB Requests 5-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.1 Get Bootcode Status 5-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.2 Execute Firmware 5-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.3 Get Firmware Revision 5-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.4 Prepare for Header Update 5-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4 Update Header 5-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5 Reboot 5-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6 Force Execute Firmware 5-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.7 External Memory Read 5-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents
vi
5.8 External Memory Write 5-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.9 I2C Memory Read 5-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.10 I2C Memory Write 5-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.11 Internal ROM Memory Read 5-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 Programming Considerations and Bootcode File List 6-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1 Programming Considerations 6-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.1 USB Requests 6-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.2 Interrupt Handling Routine 6-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2 File List 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2.1 Bootcode.c Main Program 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2.2 I2C.c I2C Routines 6-25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3 header.c I2C Header Routines 6-32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.4 tusb5052.h UMP-Related Header File 6-38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.5 usb.h USB-Related Header File 6-52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.6 types.h Type Definition Header File 6-55. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7 i2c.h I2C-Related Header File 6-56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.8 header.h I2C Header-Process-Related Header File 6-58. . . . . . . . . . . . . . . . . . . . . . . . . .

Contents
vii

1−1 Main Routine 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1−2 Interrupt Service Routine 1-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1−3 Control (Setup) Endpoint Handler 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1−4 Input Endpoint 0 Interrupt Handler 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1−5 Output Endpoint 0 Interrupt Handler 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1−6 Output Endpoint 1 Interrupt Handler 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−1 Control Write Transfer With Data 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−2 Control Read Without Data 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−3 Control Read 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2−1 Boot Code Response to Control Write Without Data 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−2 Boot Code Response to Control Read 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−1 Hub Descriptor 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−2 Device Descriptor 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−3 Configuration Descriptor 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−4 Interface Descriptor 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−5 Interrupt Endpoint 1 Descriptor 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−6 Device Descriptor 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−7 Configuration Descriptor 4-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−8 Interface Descriptor 4-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−9 Output Endpoint 1 Descriptor 4-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5−1 USB Info Basic Descriptor 5-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5−2 USB Info Basic and Firmware Basic Descriptor 5-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6−1 Vector Interrupt Values and Sources 6-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

viii

1-1
Introduction

Chapter 1 illustrates the bootcode process with bootcode flow charts. It
contains a description of the TUSB5052 bootcode document main program
and a flow chart of the interrupt service routine, control (setup) endpoint
handler, input endpoint 0 interrupt handler, output endpoint 0 handler, and the
output endpoint 1 handler.
Topic Page
1.1 Bootcode Main Program 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Interrupt Service Routine 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Control (Setup) Endpoint Handler 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Input Endpoint 0 Interrupt Handler 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5 Output Endpoint 0 Handler 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.6 Output Endpoint 1 Handler 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 1

Bootcode Main Program
1-2
1.1 Bootcode Main Program
After power-on reset, the bootcode copies predefined USB descriptors to the
shared RAM. The first USB descriptor is the device descriptor. It describes the
embedded function class, vendor ID, product ID, etc. The second USB
descriptor is the configuration descriptor, which contains information such as
how the device is powered, the number of configurations available, type and
number of interfaces, and end-point descriptors. From these two descriptors,
Windows loads the necessary device drivers and performs pertinent actions.
Vendor and product IDs are crucial to the bootcode. Windows gets VID and
PID through the standard USB device request and then tries to match the two
IDs with its own database. If Windows finds them in the database, it loads the
corresponding device driver. If it is not able to match the IDs it provides a
prompt directing the user to provide the driver disks, which contain the INF
files.
Once the bootcode finishes copying descriptors, it looks for the EEPROM on
the I2C port. If a valid signature is found, it reads the data type byte. If the data
type is application code, it downloads the code to an external data space. Once
the code is loaded and the checksum is correct, bootcode releases control to
the application code. If the data contains USB device information, the
bootcode interprets the data and copies it to hub registers and to the
embedded function device descriptor, if the checksum is correct. If the data
does not contain USB device information, bootcode restores predefined
settings to the hub register and device descriptor.
After the bootcode updates the hub register and device descriptor, it sets up
for a USB transaction and connects itself to the USB. It remains there until the
host drivers download the application code. Once complete, it disconnects
from the USB and releases control to the application code. Figure 1−1
illustrates bootcode operation.

Bootcode Main Program
1-3
Introduction
Figure 1−1.Main Routine
Copy default descriptors and
initialize necessary variables
Does EEPROM
contain valid
signature?
No
Yes
Does EEPROM
contain
firmware?
Read and copy VID and PID
from EEPROM to TUSB5052
Download firmware to xdata RAM
Yes
USB data initialization
No
Is firmware
loaded and ready
to run?
No
Disable all interrupts and switch
xdata space to code space
Run firmware
Yes
Load firmware
from USB

Interrupt Service Routine
1-4
1.2 Interrupt Service Routine
Interrupt service is generated from external interrupt 0. TUSB5052 uses this
interrupt for internal peripherals. This interrupt consists of input/output
endpoints, setup packet, I2C, UART, printer port, and DMA.
The main service routine confirms the source of interrupt then notifies
corresponding functions. Once interrupt is performed, the main service routine
clears INTVEC registers to inform hardware that the service is complete, then
releases control back to the main program. Figure 1−2 illustrates how each
service is processed.

Interrupt Service Routine
1-5
Introduction
Figure 1−2.Interrupt Service Routine
Is output
endpoint 0
interrupt?
No
Yes
No
End of interrupt
Output endpoint 1 handler
Disable global interrupt
Is output
endpoint 1
interrupt?
Yes Output endpoint 0 handler
Yes
No
Input endpoint 0 handler
Is input
endpoint 0
interrupt?
Yes
No
Setup packet interrupt handler
Is setup
packet received
interrupt?
Clear interrupt vector and
enable global interrupt

Control (Setup) Endpoint Handler
1-6
1.3 Control (Setup) Endpoint Handler
Once bootcode receives a setup packet from the host, a control packet
interrupt handler acquires control from the interrupt service routine. This
handler processes the incoming packet, performs the appropriate action, then
returns control to the interrupt service routine, as shown in Figure 1−3.
Figure 1−3.Control (Setup) Endpoint Handler
End of interrupt
Setup packet handler
Stall IEP0 if the incoming setup
packet is illegal
Process standard USB
request and configuration
1.4 Input Endpoint 0 Interrupt Handler
Figure 1−4 illustrates the process of sending data back to the host. If the last
packet is sent, the handler stalls the input endpoint, which prevents the host
from getting more data.
Figure 1−4.Input Endpoint 0 Interrupt Handler
Is this
the last
packet?
Yes
No
End of interrupt
Input endpoint 0 handler
In data stage now, call
FillEp0TxFifoWithNextDataPacket()
routine to send out next data packet
The last packet was sent. Stall IEP0.
If host asks for more data, bootcode
will stall. This scheme works fine even
in status stage because stall will be
clear once setup packet is received.

Output Endpoint 0 Handler
1-7
Introduction
1.5 Output Endpoint 0 Handler
Figure 1−5 demonstrates the process bootcode uses to deal with an output
endpoint 0 interrupt. Because bootcode does not support control write with a
data stage, it merely clears the NAK bit in the handler.
Figure 1−5.Output Endpoint 0 Interrupt Handler
End of interrupt
Output endpoint 0 handler
Clear NAK bit Bootcode does not support control
write with data stage. Therefore, this
interrupt only happens in status stage
of control read. Clear the NAK bit in
OEP0 so next OEP0 can receive next
OUT packet in status stage, or
bootcode does nothing.
1.6 Output Endpoint 1 Handler
The application code is downloaded from output endpoint 1, as shown in
Figure 1−6. This endpoint supports double buffered. Therefore, it switches to
the other buffer as soon as the current buffer receives data from the host.
Figure 1−6.Output Endpoint 1 Interrupt Handler
End of interrupt
Output endpoint 1 handler
Get the size of incoming packet
from current buffer and copy
it to xdata RAM
Switch the pointer to the other
buffer. Clear the NAK in
original buffer.

1-8

2-1
TUSB5052 USB Firmware Flow
   
There are three types of control transfers in standard USB requests.
Figure 2−1 through Figure 2−3 and Table 2−1 and Table 2−2 demonstrate the
process bootcode uses to respond to each control transfer.
Topic Page
2.1 Control Write Transfer With Data 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Control Write Without Data 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Control Read Transfer 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 2

Control Write Transfer With Data (Bootcode does not support this)
2-2
2.1 Control Write Transfer With Data (Bootcode does not support this)
Figure 2−1.Control Write Transfer With Data
SETUP(0) OUT(1) OUT(0) OUT(0/1) IN(1)
INT INT INT INT
More
packets
Setup stage Data stage Status stage
1. Hardware generates interrupt
2. Set NAK on both endpoints.
3. Set DIR bit in USBCTL to
4. Decode the setup packet.
5. If another setup packet
arrives, abandon this one.
6. Execute appropriate routines.
a) Clear NAK bit in OUT
endpoint.
b) Clear NAK bit in IN endpoint
for status stage.
.
1. Hardware generates interrupt to
MCU.
2. Copy data from OUT buffer.
3. Clear the NAK bit.
4. If all data has been received,
stall output endpoint.
.
1. Hardware handles this but
does not generate interrupt
to MCU.
to MCU.
indicate the data direction
and SIR bit to indicate setup
interrupt is being served.
2.2 Control Write Without Data
Table 2−1.Boot Code Response to Control Write Without Data
Control Write Without Data Action In Boot Code
Clear feature of device Stall endpoint
Clear feature of interface Stall endpoint
Clear feature of endpoint Clear stall on requested endpoint
Set feature of device Set remote wake-up feature
Set feature of interface Stall endpoint
Set feature of endpoint Stall requested endpoint
Set address Set device address
Set descriptor Stall endpoint
Set configuration Set bConfiguredFlag
Set interface Stall endpoint
Synchronization frame Stall endpoint

Control Read Transfer
2-3
TUSB5052 USB Firmware Flow
Figure 2−2.Control Read Without Data
SETUP(0) IN(1)
INT
Setup stage Status stage
1. Hardware generates interrupt
to MCU.
2. Set NAK on both endpoints.
3. Set DIR bit in USBCTL to
indicate the data direction
and SIR bit to indicate setup
interrupt is being served.
4. Decode the setup packet.
5. If another setup packet
arrives, abandon this one.
6. Execute appropriate routines.
a) Clear NAK bit in OUT
endpoint.
b) Clear NAK bit in IN endpoint
for status stage.
.
1. Hardware handles this but
does not generate interrupt
to MCU.
2.3 Control Read Transfer
Table 2−2.Boot Code Response to Control Read
Control Read Action In Boot Code
Get status of device Return remote wake-up and power status
Get status of interface No action and return zero
Get status of endpoint Return the endpoint status (stall or not)
Get descriptor of device Return device descriptor
Get descriptor of configuration Return configuration descriptor
Get descriptor of string Illegal requests, stall endpoint
Get descriptor of interface Illegal requests, stall endpoint
Get descriptor of endpoint Illegal requests, stall endpoint
Get configuration Return bConfiguredFlag value
Get interface No action and return zero

Control Read Transfer
2-4
Figure 2−3.Control Read
SETUP(0) IN(1) IN(0) IN(0/1) OUT(1)
INT INT INT INT
Setup stage Data stage Status stage
1. Hardware generates interrupt
2. Set NAK on both endpoints.
3. Set DIR bit in USBCTL to
4. Decode the setup packet.
5. If another setup packet
6. Execute appropriate routines.
a) Clear NAK bit in OUT
endpoint for status stage.
b) Copy data to IN endpoint
buffer and set byte count.
.
1. Hardware generates interrupt to
MCU.
2. Copy data to IN buffer.
3. Clear the NAK bit.
4. If all data has been received,
stall IN endpoint.
.
1. Hardware handles this but
does not generate interrupt
to MCU.
to MCU.
indicate the data direction
and SIR bit to indicate setup
interrupt is being served.
arrives, abandon this one.
More
packets