CY3240-I2USB
USB-I2C Bridge Guide
Doc. # 001-66660 Rev.*B
Cypress Semiconductor
198 Champion Court
San Jose, CA 95134-1709
Phone (USA): 800.858.1810
Phone (Intnl): 408.943.2600
http://www.cypress.com
Copyrights
Copyrights
© Cypress Semiconductor Corporation, 2011-2013. The information contained herein is subject to change without notice.
Cypress Semiconductor Corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a
Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted
nor intended to be used for medical, life support, life saving, critical control or safety applications, unless pursuant to an
express written agreement with Cypress. Furthermore, Cypress does not authorize its products for use as critical components
in life-support systems, where a malfunction or failure may reasonably be expected to result in significant injury to the user.
The inclusion of Cypress products in life-support systems application implies that the manufacturer assumes all risk of such
use, and in doing so indemnifies Cypress against all charges.
Any Source Code (software and/or firmware) is owned by Cypress Semiconductor Corporation (Cypress), and is protected
by, and subject to worldwide patent protection (United States and foreign), United States copyright laws, and international
treaty provisions. Cypress hereby grants to licensee a personal, non-exclusive, non-transferable license to copy, use, modify,
create derivative works of, and compile the Cypress Source Code and derivative works for the sole purpose of creating
custom software and/or firmware in support of licensee product to be used only in conjunction with a Cypress integrated
circuit as specified in the applicable agreement. Any reproduction, modification, translation, compilation, or representation of
this Source Code except as specified above is prohibited without the express written permission of Cypress.
Disclaimer: CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS
MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE. Cypress reserves the right to make changes without further notice to the materials
described herein. Cypress does not assume any liability arising out of the application, or use of any product or circuit
described herein. Cypress does not authorize its products for use as critical components in life-support systems, where a
malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product
in a life-support systems application implies that the manufacturer assumes all risk of such use, and in doing so indemnifies
Cypress against all charges.
Use may be limited by and subject to the applicable Cypress software license agreement.
PSoC Designer™ and Programmable System-on-Chip™ are trademarks and PSoC® is a registered trademark of Cypress
Semiconductor Corp. All other trademarks or registered trademarks referenced herein are property of the respective
corporations.
Flash Code Protection
Cypress products meet the specifications contained in their particular Cypress PSoC Data Sheets. Cypress believes that its
family of PSoC products is one of the most secure families of its kind on the market today, regardless of how they are used.
There may be methods, unknown to Cypress, that can breach the code protection features. Any of these methods, to our
knowledge, would be dishonest and possibly illegal. Neither Cypress nor any other semiconductor manufacturer can
guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as "unbreakable."
Cypress is willing to work with the customer who is concerned about the integrity of their code. Code protection is constantly
evolving. We at Cypress are committed to continuously improving the code protection features of our products.
2
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Contents
1. Introduction
1.1
1.2
1.3
1.4
Kit Contents .................................................................................................................5
1.1.1 Prerequisites ....................................................................................................5
Additional Learning Resources....................................................................................6
Document History ........................................................................................................6
Documentation Conventions .......................................................................................6
2. Getting Started
2.1
2.2
2.3
2.4
3.3
5.2
25
System Block Diagram ..............................................................................................25
Functional Description ...............................................................................................26
4.2.1 PSoC CY8C24894 Chip.................................................................................27
4.2.2 USB Mini B Connector ...................................................................................28
4.2.3 ISSP Programming Header............................................................................28
4.2.4 GPIO Pins ......................................................................................................29
4.2.5 I2C Slave Interface Connector .......................................................................30
4.2.6 Demo Board ...................................................................................................31
5. Code Examples
5.1
17
Introduction ................................................................................................................17
Connect Bridge to Device ..........................................................................................17
3.2.1 Program USB-I2C Bridge...............................................................................18
Connect Demonstration Board to Bridge ...................................................................19
3.3.1 Run Demonstration Board Test ......................................................................19
4. Hardware
4.1
4.2
9
Kit Installation ..............................................................................................................9
PSoC Designer ..........................................................................................................13
PSoC Programmer ....................................................................................................14
Bridge Control Panel..................................................................................................15
3. Kit Operation
3.1
3.2
5
33
My First Code Example .............................................................................................33
5.1.1 Project Objective ............................................................................................33
5.1.2 USB-I2C Demo Board Flowchart ...................................................................34
5.1.3 Creating My First PSoC 1 Project ..................................................................35
5.1.4 Verify Output ..................................................................................................51
USBtoIIC Code Example ...........................................................................................53
5.2.1 Project Description .........................................................................................53
5.2.2 PSoC Designer Interconnected View .............................................................54
5.2.3 USBtoIIC Flowchart........................................................................................55
5.2.4 Verify Output ..................................................................................................57
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3
Contents
A. Appendix
A.1
A.2
A.3
4
59
Schematic.................................................................................................................. 59
A.1.1 USB-I2C Bridge Schematic............................................................................ 59
A.1.2 Demo Board Schematic ................................................................................. 61
USB-I2C Bridge Board Layout................................................................................... 62
A.2.1 Demo Board Layout ....................................................................................... 62
Bill of Materials (BOM)............................................................................................... 63
A.3.1 USB-I2C Bridge BOM .................................................................................... 63
A.3.2 Demo Board................................................................................................... 64
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
1.
Introduction
Thank you for your interest in the CY3240 USB-I2C Bridge Kit. The CY3240 USB-I2C Bridge can be
used with the Bridge Control Panel that is installed with PSoC Programmer. The kit is designed to
test, tune, and debug programs that have an I2C slave interface. This document describes the working of the CY3240 USB-I2C Bridge and includes code examples, which will help you get started with
the bridging tool. You can also develop custom programs using PERL, Python, C++, and C# languages. These custom applications allow generating complex testing, debugging, and validation
systems using PSoC Programmer.
You can evaluate the kit using the code examples provided with the kit. The code examples help to:
■
Explore I2USB communication between the PC and the slave, interfaced via I2C slave interface
connector of the bridge
■
Customize the designs provided along with the kit
The CY3240 USB-I2C Bridge board is configured with the “USBtoIIC” code example when shipped.
The I2C demo board is configured with “My First Code Example”. See Chapter 5 for details. Evaluate
the examples provided with the kit and then experiment with the kit hardware and software to create
your own designs.
1.1
Kit Contents
The CY3240 USB-I2C Bridge Kit contains:
■
USB-I2C Bridge
■
I2C demo board with temperature and ambient light sensor
■
USB A to Mini B cable
■
CY3240 USB-I2C Bridge kit CD
❐
PSoC Designer installation file
❐
PSoC Programmer installation file
❐
Bridge Control Panel installation file (packaged along with PSoC Programmer)
❐
Code examples
❐
Hardware file
❐
Kit guide
❐
Quick start guide
❐
Release notes
Inspect the contents of the kit. If any parts are missing, contact your nearest Cypress sales office for
further assistance.
1.1.1
Prerequisites
The CY3217-MiniProg1 kit is required to reprogram the CY3240 USB-I2C Bridge and I2C demo
board. MiniProg is a small and compact programming tool that connects to your PC using the
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
5
Introduction
provided USB 2.0 cable. During prototyping, the MiniProg can be used as an in-system serial
programmer (ISSP) to program all PSoC 1 devices on your PCB. This kit can be purchased from
http://www.cypress.com/go/CY3217-MiniProg1.
1.2
Additional Learning Resources
Visit www.cypress.com for additional learning resources in the form of data sheets, technical
reference manual, and application notes.
1.3
■
Application Note - I2C-USB Bridge Usage
http://www.cypress.com/?rID=2853
■
Application Note - Using Cypress I2C Port Expander with Flash Storage:
http://www.cypress.com/?rID=2694
■
PSoC CY8C24894 - Features and Chip functionality:
http://www.cypress.com/?rID=37765
■
PSoC CY8C21123 - Features and Chip functionality:
http://www.cypress.com/?rID=3335
■
For more information regarding PSoC Designer functionality and releases:
www.cypress.com/go/psocdesigner
■
For more information regarding PSoC Programmer, supported hardware and COM layer:
www.cypress.com/go/psocprogrammer
■
For a list of PSoC Designer-related trainings:
http://www.cypress.com/?rID=40543
Document History
**
PDF Creation
Date
01/25/2011
Origin of
Change
RKPM
*A
04/14/2011
RKPM
*B
01/17/2013
KUK
Revision
1.4
Description of Change
Initial version of kit guide
Added My First Code Example section. Content edits
throughout the document
Updated images in sections 2 and 5 and minor content
updates through the document.
Documentation Conventions
Table 1-1. Document Conventions for Guides
Convention
6
Usage
Courier New
Displays file locations, user entered text, and source code:
C:\ ...cd\icc\
Italics
Displays file names and reference documentation:
Read about the sourcefile.hex file in the PSoC Designer User Guide.
[Bracketed, Bold]
Displays keyboard commands in procedures:
[Enter] or [Ctrl] [C]
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Introduction
Table 1-1. Document Conventions for Guides
Convention
Usage
File > Open
Represents menu paths:
File > Open > New Project
Bold
Displays commands, menu paths, and icon names in procedures:
Click the File icon and then click Open.
Times New Roman
Displays an equation:
2+2=4
Text in gray boxes
Describes cautions or unique functionality of the product.
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
7
Introduction
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2.
Getting Started
This chapter describes the installation and configuration of the CY3240 USB-I2C Bridge kit.
2.1
Kit Installation
To install the kit software, follow these steps:
1. Insert the kit CD into the CD drive of your PC. The CD is designed to auto-run and the kit installer
startup screen appears.
Note You can also download the latest kit installer from http://www.cypress.com/go/CY3240I2USB. Three different types of installers are available for download.
a. CY3240 USB-I2C Bridge_ISO: This file (ISO image) is an archive of the optical disc provided
with the kit. You can use this to create an installer CD or extract information using WinRar or
similar tools.
b. CY3240 USB-I2C Bridge_ Single Package: This executable file installs the kit CD contents,
including PSoC Programmer, PSoC Designer, code examples, hardware files, and user documents.
c. CY3240 USB-I2C Bridge_Single Package (without prerequisites): This executable file installs
only the kit contents, which includes kit code examples, hardware files, and user documents.
2. Click Install CY3240 USB-I2C Bridge to start the installation, as shown in Figure 2-1.
Figure 2-1. CY3240 USB-I2C Bridge Kit Menu
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9
Getting Started
Note If auto-run does not execute, double-click cyautorun.exe file on the root directory of the
CD, as shown in Figure 2-2.
Figure 2-2. Root Directory of CD
3. On the startup screen, click Next to start the installer.
4. In the InstallShield Wizard, choose the folder location to install the setup files. You can change
the location of the folder using Change, as shown in Figure 2-3.
5. Click Next to launch the installer.
Figure 2-3. InstallShield Wizard
6. On the Product Installation Overview screen, select the installation type that best suits your
requirement. The drop-down menu has three options: Typical, Complete, and Custom, as
shown in Figure 2-4.
7. Click Next to start the installation.
10
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Getting Started
Figure 2-4. Installation Type Options
8. When the installation begins, a list of packages appears on the Installation Page.
9. A green check mark appears adjacent to every package that is downloaded and installed, as
shown in Figure 2-5.
10.Wait until all the packages are downloaded and installed successfully.
Figure 2-5. Installation Page
11. Click Finish to complete the installation, as shown in Figure 2-6.
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
11
Getting Started
Figure 2-6. Installation Complete Page
After the software installation, verify that you have all hardware and drivers set up for the CY3240
USB-I2C Bridge kit by connecting the bridge to your PC via its USB interface. Because this is the
first time you have connected this board to the PC, initial drivers are installed. Follow the instructions
to complete the installation process. Also, verify your installation by opening PSoC Programmer with
the CY3240 USB-I2C Bridge board attached to the USB port of the PC.
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Getting Started
2.2
PSoC Designer
PSoC Designer is the revolutionary integrated design environment (IDE) that helps to customize
PSoC to meet your specific application requirements. PSoC Designer software accelerates system
bring-up and time-to-market.
1. To open PSoC Designer, click Start > All Programs > Cypress > PSoC Designer <version> >
PSoC Designer <version>
2. To create a new project, click File > New Project
3. To open an existing project, click File > Open
4. To experiment with the code examples, go to Code Examples on page 33
Figure 2-7. PSoC Designer Interconnect View
Note For more details on PSoC Designer, see the PSoC Designer IDE Guide located at:
<Install_Directory>:\Cypress\PSoC Designer\<version>\Documentation.
You can also see the PSoC Designer Quick Start Guide at: http://www.cypress.com/?rID=47954
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13
Getting Started
2.3
PSoC Programmer
To open PSoC Programmer, click Start > All Programs > Cypress > PSoC Programmer <version> > PSoC Programmer <version>.
To successfully program the device, follow these steps:
1. Select the MiniProg1 in Port Selection, as shown in Figure 2-8.
Figure 2-8. PSoC Programmer Window
2. Click the File Load button to load a hex file.
3. Click the Program button to program the hex file into the chip.
4. Close PSoC Programmer.
For more details on PSoC Programmer, see the user guide at the following location:
<Install_Directory>:\Cypress\Programmer\<version>\Documents
14
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Getting Started
2.4
Bridge Control Panel
The Bridge Control Panel is used with CY3240 USB-I2C Bridge to enable communication with I2C
slave devices. This program is used to configure I2C devices and also to acquire and process data
received from I2C slave devices. The Bridge Control Panel helps in optimizing, debugging, and calibrating the target application.
1. Click Start > All Programs > Cypress > Bridge Control Panel <version> > Bridge Control
Panel.
2. Select Power Supply, as highlighted in Figure 2-9.
3. Select the port connectivity bridge from the Connected I2C/SPI-USB converters.
Figure 2-9. Select Bridge
Note For more information, go to Bridge Control Panel > Help > Help Contents.
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15
Getting Started
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CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
3.
3.1
Kit Operation
Introduction
This chapter provides key information regarding the CY3240 USB-I2C Bridge specifications. It also
gives a brief overview of how to verify that you have set up the kit correctly. The device meets the
requirements of the I2C Specifications for standard and fast speed I2C devices, and supports USB
human interface devices (HID). The bridge is powered by the USB and consumes less than 500 mA.
The device can be configured for several I2C clock rates such as 50 kHz, 100 kHz, and 400 kHz.
The number of devices that can be connected is constrained only by the I2C address limit and physical ability of the I2C bus. For more details, see the I2C Specifications.
The USB communication function uses two 64-byte packets: one for input data flow and the other for
output data flow. The maximum bandwidth of this configuration is 64 bytes. This is sufficient for most
USB-I2C bridge applications (Figure 3-1).
Figure 3-1. USB-I2C Bridge
I2C Slave
Device
USB
I2C
2
USB-I C Bridge
I2C Slave
Device
I2C Slave
Device
3.2
Connect Bridge to Device
Figure 3-2. Simplified Schematic of USB-I2C Bridge
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17
Kit Operation
Perform the following steps to connect the device to CY3240 USB-I2C Bridge, as shown in
Figure 3-2:
1. Connect GND of the device to GND of the bridge.
2. Connect the SDA and SCL lines to the bridge.
The CY3240 USB-I2C Bridge has 2.2 k pull-up resistors connected to +5 V. The INT pin is a pulldown bidirectional pin that can be used as an additional signal between the bridge and the I2C
slave device for functions such as sleep mode control.
3. Power the device from the Vdd pin on the bridge, if it does not have its own power supply. Note
that the Vdd connection between the bridge and demo board is required, even if the board is selfpowered. Optionally, the bridge can provide 3.3 V or 5 V, or work with an externally powered
board using 2.4 V to 5.6 V.
4. When the connection between the bridge and USB is successful, the LED (green) lights up, as
shown in Figure 3-3.
Figure 3-3. Connecting Bridge to USB.
5. Open the Bridge Control Panel from the PC to work with the bridge.
3.2.1
Program USB-I2C Bridge
The CY3240 USB-I2C Bridge can be programmed using a MiniProg at the programming header of
the bridge. To use MiniProg, use the ISSP programming header (J2) on the board, as highlighted in
Figure 3-4.
Figure 3-4. ISSP Programming Header
18
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Kit Operation
3.3
Connect Demonstration Board to Bridge
1. Connect the I2C slave demonstration board to the bridge, as shown in Figure 3-5.
Figure 3-5. Demonstration Board and Bridge Connection
2. Select +5 V as power supply to the board from the Bridge Control Panel and click on the Toggle
Power button. The LED (red) on the bridge board lights up, as shown.
Figure 3-6. LED (Red) on the Bridge Board
3. Click List; the bridge will find the I2C slave demonstration board at 0x00 address.
3.3.1
Run Demonstration Board Test
The demonstration board has a built-in temperature sensor and photo diode. The measurement
results of these are sent over I2C.
1. Open the Variable Setting dialog box from the Chart menu.
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19
Kit Operation
Figure 3-7. Variable Setting Box
2. The demo.ini file initializes light and temperature variables. Load the demo.ini file by following
these steps:
a. Click the Load button, as shown in Figure 3-7
b. Navigate to <Install_Directory>:\Cypress\CY3240 USB-I2C Bridge Kit\<version> \Firmware\Configuration files
c. Select demo.ini
d. Click Open
e. Click OK
3. The demo.iic file contains the iic commands that can be sent to the demo board. Load the
demo.iic file by following these steps:
a. Click on the Open Commands File button
b. Navigate to <Install_Directory>:\Cypress\CY3240 USB-I2C Bridge Kit\<version> \Firmware\Configuration files
c. Select demo.iic
d. Click Open
4. The first two lines in the demo.iic file show how to control the LEDs on the board. If the two red
LEDs do not light up, click on the Toggle Power button. Position the cursor in the first line and
press [Enter] to send the command. Repeat for the second command line. Observe that, on
sending the first command, LED1 turns off. The second command reduces the intensity of LED2
by 50 percent. Experiment with the intensity settings.
20
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Kit Operation
Figure 3-8. Bridge Control Panel Editor Screen View
5. Click in the last line, which reads temperature and light data from the device and then click the
Repeat button. On clicking Repeat, the command that is sent last is repeated until Stop is
clicked. This makes data collection easier. The data received from slave can be viewed either
graphically or in a tabular form.
6. Click the Chart tab to view the data graphically, as shown in Figure 3-9. Experiment with displaying only temperature or only light.
7. Move your hand over the photo diode on the demo board to vary the light intensity; relative values are reflected on the graph. Similarly, vary the temperature around the board by placing a hot
or cold object near the board and observe that the temperature values varies accordingly.
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21
Kit Operation
Figure 3-9. Bridge Control Panel Graphical Screen View
8. Click the Stop button to stop scanning.
9. Click the Table tab to view data in a tabular form, as shown in Figure 3-10.
22
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Kit Operation
Figure 3-10. Bridge Control Panel Tabular Screen View
The File menu has these options:
■
Save Send Data - To save data sent to the demo board from the Bridge Control Panel.
■
Save Receive Data - To save received data shown on the status window of the Bridge Control
Panel.
Go to Bridge Control Panel Help from the Help menu for more information on the Bridge Control
Panel and iic command format.
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Kit Operation
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4.
Hardware
This section provides an overview of the hardware, including power system, jumper setting, and programming interface. To start using the board, go to Code Examples on page 33.
4.1
System Block Diagram
The CY3240 USB-I2C Bridge kit has two boards:
■
USB-I2C Bridge board
■
Demo board
The USB-I2C Bridge board consists of:
■
PSoC CY8C24894 chip
■
USB Mini B connector
■
ISSP programming header
■
GPIO pins
■
I2C slave connector
Figure 4-1. USB-I2C Bridge Board
ISSP
Programming
Header
I2C Slave
Connector
PSoC
CY8C24894
USB Mini B Connector
(Communication and
Power Supply of
3.3V/5V)
GPIO Pins
Demo board consists of:
■
CY8C21123 chip
■
LED
■
Photo diode
■
ISSP programming header or data connector (with I2C lines)
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25
Hardware
Figure 4-2. Demo Board
ISSP
Programming
Header/Data
connector
Photo-diode
4.2
PSoC
CY8C21123
LED
Functional Description
The USB-I2C Bridge is connected to the PC in the same way as an HID device. It requires no
additional driver when connected to a PC installed with Windows. This USB-I2C Bridge works as a
master in the I2C bus and is controlled by the PC program via USB. In addition, a demonstration PC
program is included with the project to demonstrate bridge operation with connected I2C slave.
Figure 4-3. USB-I2C Bridge with Demo Board
Internal Power Jumper
USB Mini-B Connector
Photo Diode
Output LEDs
PSoC CY8C24894 Chip
GPIO Pins
PSoC CY8C21123 Chip
ISSP Programming Header
26
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Hardware
4.2.1
PSoC CY8C24894 Chip
The PSoC CY8C24894 on the CY3240 USB-I2C Bridge board is preprogrammed to function as a
full-featured, full-speed (12 Mbps) USB, and an I2C master. This device enables creating customized peripheral (I/O) configurations that match the requirements of individual applications.
The PSoC device also performs the following functions:
■
Lights up LED (green) on connecting the bridge to the host via USB
■
Lights up LED (red) on external power supply to the target device
■
Acts as an interface between the host and the target device
Figure 4-4. PSoC CY8C24894 Hardware Schematic
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27
Hardware
4.2.2
USB Mini B Connector
USB Mini B connector communicates between the PC and the bridge. It is used to power up the
bridge and supply a voltage range of 3.3 V or 5 V to the demo board. These plugs are always
oriented downstream towards the USB device. It has SN65220, a single transient voltage
suppressor, to provide electrical noise transient protection to the USB port.
Figure 4-5. USB Mini Port Schematic
4.2.3
ISSP Programming Header
The in-system serial programming header is used to:
■
Burn the hex code onto the chip
■
Connect the MiniProg to program the chip
The ISSP connector consists of the following:
Table 4-1. ISSP Header Connection Details
28
Pin No
Connection
Description
1
+V Device
To supply voltage to the bridge
2
GND
3
INT
Ground pin of the bridge
Interrupt pin
4
SCL
Serial clock line
5
SDA
Serial data line
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Hardware
Figure 4-6. ISSP Header Schematic
4.2.4
GPIO Pins
GPIO plays an important role in customizing the applications.
Table 4-2. GPIO Pin Connectivity Table
Terminal Connection
Port
Pin No.
TP12
P2[4]
43
External analog ground (AGND) input
TP11
P2[6]
44
External voltage reference (VREF) input
TP10
P0[0]
45
Analog column mux input
TP9
P0[2]
46
Analog column mux input
TP8
P0[4]
47
Analog column mux input
TP7
P0[6]
48
Analog column mux input
TP6
P0[7]
51
Analog column mux input
TP5
P0[5]
52
Analog column mux input and column output
TP4
P0[3]
53
Analog column mux input and column output
TP3
P0[1]
54
Analog column mux input
TP2
P2[7]
55
GPIO
TP1
P2[5]
56
GPIO
TP13
P2[2]
42
GPIO
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Description
29
Hardware
Figure 4-7. GPIO Pin Schematic
4.2.5
I2C Slave Interface Connector
The I2C slave interface connector is used to communicate data between the target device and the
bridge board. It consists of two devices, MAX3378 and SN721.
MAX3378
■
Is used to convert voltage level between the target device (Vcc) and the host level voltage (VL)
■
Has bidirectional level translation, accepts VL +1.2 V (Min) to +5.5 V (Max); Vout (High) is 0.6
times VL (if source current is 0.02 mA) and Vout (Low) is 0.4 V
SN721
■
30
An array of SCR/diode bipolar structure for ESD and over-voltage protection
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Hardware
Figure 4-8. I2C Slave Interface Schematic
4.2.6
Demo Board
The demo board lights the two LEDs upon receiving data from the host and transfers the data,
acquired from the photo diode to the host.
The PSoC device (CY8C21123) is used to control the two LEDs based on input from the host using
the Bridge Control Panel. The PSoC device updates the I2C register with the sensor information,
which can be read by any I2C master.
Table 4-3. CY8C21123 Pin Connectivity
Pin No.
Port No
Description
6
P0[4]
LED1
7
P0[2]
LED2
1
P0[5]
Photo-diode
8
P1[0]
Voltage supply
3
P1[1]
Ground
2
P0[3]
Interrupt
5
Vcc
Serial clock
4
GND
Serial data
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
31
Hardware
Figure 4-9. Demo Board Chip Schematic
32
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
5.
Code Examples
All code examples are available in the CY3240 USB-I2C Bridge kit CD or at the following location:
<Install_Directory>:\Cypress\CY3240 USB-I2C Bridge Kit\<version>\Firmware.
5.1
My First Code Example
5.1.1
Project Objective
This code example demonstrates data transfer between the demo board and the host using I2C
communication. The demo board outputs temperature and light data to the host whenever the host
requests this data. Similarly, the host board sends commands to the demo board to control the LEDs
on the board.
The demo board has a photo diode to measure the light intensity. The voltage value analogous to
the die temperature is available on a PSoC analog block array. This temperature input can be used
in applications such as battery chargers and data acquisition without any external components. In
this code example, this temperature input is used to read the die temperature value. See the Technical Reference Manual available in Help > Documentation for more details.
The following user modules are used in the design to achieve the objective of this project:
ADC10: Used to obtain the digital values for light intensity and temperature. Input to the ADC module is switched between light input and temperature input once every 551 scan cycles.
EzI2C: Used to configure the PSoC on the demo board as I2C slave and to transfer data to the
bridge board where the PSoC is configured as I2C master.
PWM8: Used to handle the LED command from the host and vary the LED intensity accordingly.
When data is requested by the I2C master, the ADC values analogous to the die temperature and
light intensity incident on the board are output.
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
33
Code Examples
5.1.2
USB-I2C Demo Board Flowchart
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CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
5.1.3
Creating My First PSoC 1 Project
1. Open PSoC Designer.
2. To create a new project, click File > New Project.
3. In the New Project window, select the chip-level icon. Name the project
Example_My_First_PSoC_Project, as shown in Figure 5-1.
4. Click Browse to navigate to the directory in which the project is created.
Figure 5-1. New Project Window
5. In the project creation drop down menu select new project.
6. In the Select Target Device option, click Device Catalog, as shown in Figure 5-2.
Figure 5-2. Select Project Type
7. The Device Catalog window opens and then scroll down to the CY8C21123, CY8C21223,
CY8C21323 section.
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
35
Code Examples
8. For this project, click CY8C21123-24SXI; then click Select.
Figure 5-3. Device Catalog Window
9. In the Generate 'Main' File Using: option, select C, then click OK.
36
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
10.By default, the project opens in Chip view, as shown in Figure 5-4.
Figure 5-4. Default View
11. Configure the modules required for this design. Also, connect the modules together and to the
pins on the PSoC. In the User Modules section, expand the ADCs folder.
Figure 5-5. User Modules Window
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
37
Code Examples
12.In this folder, right-click on ADC10 and select Place. The user module (UM) is placed, as shown
in the following figure.
Figure 5-6. Default ADC User Module Placement
13.The ADC UM is placed in ACE00 and ASE10 of the analog block. Click on Next Allowable
Placement (Figure 5-7) to change the ADC module from ACE00 to ACE01. Click on the Place
User Module icon (Figure 5-7). Similarly, change the ADC module in the digital block from
DBB00 to DCB02, as shown in Figure 5-8.
Figure 5-7. PSoC Designer Toolbar
Next Allowed Placement
Place User Module
Figure 5-8. ADC10 User Module Placement
Note A temperature-sensitive voltage, derived from bandgap sensing on the die, is buffered and
available as an analog input into the continuous time block ACE01. So, the ADC module placement is changed to ACE01 block.
38
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
14.Click on AnalogColumn_InputMUX_0 to change from Port_0_3 to Port_0_5.
Figure 5-9. Change Port Connectivity to ADC Module
15.Click on AnalogColumn_InputSelect_1 to select AnaloColumn_InputMUX_0.
Figure 5-10. Select Input Mux to ADC
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
39
Code Examples
16.Select Analog ADC Module and click on ADC Input to select AnalogColumn_InputSelect_1 to
connect the module to Port_0_5.
Figure 5-11. Select Port_0_5 to Compare ADC
17.Configure the ADC10_1 properties, as shown in Figure 5-12.
Figure 5-12. ADC10 User Module Properties
40
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
18.In the User Modules window, expand the Digital Comm folder and double-click on EzI2Cs to
place an EzI2C in the design.
Figure 5-13. User Module Window
19.By default, the EzI2C is placed at Port_1_0 and Port_1_ 1, as shown in Figure 5-14.
Figure 5-14. EzI2C User Module Placement
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
41
Code Examples
20.Default properties of EzI2C _1 is shown in the following figure.
Figure 5-15. Default EzI2C_1 Parameters
21.Configure the properties of EzI2Cs_1 and rename as EzI2Cs to build the project successfully.
Figure 5-16. EzI2C User Module Properties
22.In the User Modules window, expand the PWMs folder and double-click on PWM8 to place a
PWM8 in the design.
Figure 5-17. User Module Window
42
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
23.By default, the PWM8 is placed as shown in the following figure.
Figure 5-18. PWM Module Placement
24.In the PWM module, to connect Compare Out to P0[4], configure the lookup table (LUT) on
Row_0_Output_0 to GlobalOut (GOE[4]) bus. To do this, click on Compare Out of PWM8_1
Module to select the Row_0_Output_0, as shown in Figure 5-19.
Figure 5-19. Connect PWM8 to Output Line
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
43
Code Examples
25.Click on Row_0_Output_0 bus to open the Digital Interconnect window; configure the bus to
GlobalOutEven_4, as shown in Figure 5-20.
Figure 5-20. Select Global Output Line for Row_0_Ouput_0
26.Click on GlobalOutEven_4 bus to connect it output pin Port_0_4.
Figure 5-21. Select Global Output Even Line for Port Selection
44
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
27.Configure parameters of PWM8_1.
Figure 5-22. Parameter Window of PWM8_1
28.In the User Modules window, expand the PWMs folder and double-click on PWM8 to place a
PWM8 in the design.
Figure 5-23. User Module Window
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
45
Code Examples
29.By default, the PWM8_2 is placed, as shown in Figure 5-24.
Figure 5-24. Placement of PWM8_2 User Module
30.In the PWM Module, to connect the Compare Out to P0[2], configure the LUT on
Row_0_Output_2 to GlobalOut Even (GOE[2]) bus. To do this, click on Compare Out of
PWM8_2 Module to select the Row_0_Output_2, as shown in Figure 5-25.
Figure 5-25. Connect PWM8_2 to Row_0_Output_2 Bus
46
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
31.Click on Row_0_Output_2 bus to open the Digital Interconnect window; configure the bus to
GlobalOutEven_2.
Figure 5-26. Select Global Output Line for Row_0_Output_2 Bus
32.Select GlobalOutEven_2 bus line to configure Output Pin to Port_0_2.
Figure 5-27. Select GlobalOutputEvenline for Port Selection
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
47
Code Examples
33.Configure the parameters of PWM8_2.
Figure 5-28. Parameter Window of PWM8_2
34.Configure the Global Resources window to match the following figure.
Figure 5-29. Global Resources Window
48
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
35.Open the existing main.c file in Workspace Explorer. Replace the existing main.c content with the
content of the embedded Example_My_First_PSoC_Project_Main.c file, which is attached to this
document.
Figure 5-30. Workspace Explorer Window
36.Save the project.
37.To build the project, click Build >Generate/Build 'Example_My_First_PSoC_Project'.
38.Connect the CY3240 demo board to the PC through a MiniProg1 and program the board.
39.The board can be programmed through PSoC Designer IDE or by launching PSoC Programmer.
Note To program the board using PSoC Programmer, see PSoC Programmer on page 14.
40.To program the board through PSoC Designer follows these steps.
a. Click on Program > Program Part.
Note When programming the board through PSoC Designer, close any open instance of PSoC
Programmer.
b. In the Program Part window, set the following:
- In Port Selection drop-down box, select MiniProg1/<MIniProg_Number>; ensure it is Connected.
- Acquire Mode: Power Cycle
- Verification: Off
- Power Settings: 5.0 V
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
49
Code Examples
41.Click on the Program button to start programming the board.
Figure 5-31. Program Part Window
Toggle Power Button
Program Button
42.The programming of the board starts and the status can be observed on the progress bar.
Figure 5-32. Programming Status
43.When the programming is done successfully, the Operation Succeeded! message is displayed.
Figure 5-33. Operation Succeeded! Message
50
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
5.1.4
Verify Output
1. Connect the demo board to the bridge board.
Figure 5-34. Demo Board to Bridge Board Connection
2. Open Bridge Control Panel from Start > All Programs > Cypress > Bridge Control Panel <version> > Bridge Control Panel.
3. Select +5V as power supply to the board from the Bridge Control Panel; the red LED on the
bridge board lights up.
Figure 5-35. Bridge Control Panel
4. Verify the presence of demo.ini and demo.iic in the CY3240 USB-I2C Bridge Kit CD or
<Install_Directory>:\Cypress\CY3240 USB-I2C Bridge Kit\<version>\Firmware\ Configuration file
5. In the Bridge Control Panel, open the Variable Setting dialog box from the Chart menu.
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
51
Code Examples
6. Load the demo.ini file, by clicking the Load button to initialize light and temperature variables, as
shown in Figure 5-36.
Figure 5-36. Load Demo.ini file from Bridge Control Panel
7. In the Bridge Control Panel, click File > Open File to select the demo.iic file for iic commands.
The demo.iic file is used to transfer iic commands to the demo board, as shown in Figure 5-37.
Figure 5-37. Bridge Control Panel Loaded with demo.iic File
52
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
8. The first two lines in the demo.iic file show how to control the LEDs on the board. Position the
cursor in the first line and press [Enter] to send the command. Repeat for the second command
line. Observe that, on sending the first command, the LED1 turns off. The second command
reduces the LED intensity by 50%, as shown in Figure 5-37.
9. Vary the Intensity value in the eighth byte (hex) value of first and second command lines of the
Bridge Control Panel from 00-FF; observe the change in LED intensity on the demo board.
10.Click in the last line, which reads temperature and light data from the device. Click Repeat to
send the last command repeatedly.
11. Click the Chart tab to view the data graphically, as shown in Figure 5-38.
Figure 5-38. Bridge Control Panel with Plot of Temperature and Light Values
12.The ADC value analogous to the die temperature and light intensity incident on the board are
plotted on the Y-axis of the graph versus the sample number on the X-axis of the graph.
13.Save and close the project.
5.2
USBtoIIC Code Example
5.2.1
Project Description
This project demonstrates communication between the bridge and the host. After each packet is
received by the bridge, an acknowledgement is sent to the host before the next transfer operation
begins.
This project uses the following modules:
CMPRG: Used to compare the data programmable reference threshold.
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
53
Code Examples
PWRFB: Used to set the power level for this application.
TIMER8: Used to wake up the application from sleep mode.
5.2.2
PSoC Designer Interconnected View
Figure 5-39. Functional Bocks
54
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
5.2.3
USBtoIIC Flowchart
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Code Examples
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CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Code Examples
5.2.4
Verify Output
When connected to the demonstration board, the green LED on the bridge blinks indicating transfer
operation between the bridge and the PC.
Figure 5-40. Verify Output
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
57
Code Examples
58
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
A.
Appendix
All hardware files are available in the CY3240 USB-I2C Bridge kit CD or at the following location:
<Install_Directory>:\Cypress\CY3240 USB-I2C Bridge Kit\<version>\Hardware.
A.1
Schematic
A.1.1
USB-I2C Bridge Schematic
Figure A-1. Reverse Current Protection Schematic
Figure A-2. USB Connection with Voltage Suppressor Schematic
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
59
Figure A-3. Diode Schematic
Figure A-4. Voltage Regulator Schematic
60
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
Figure A-5. PSoC CY8C24894 Schematic
A.1.2
Demo Board Schematic
Figure A-6. Demo Board Schematic
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
61
A.2
USB-I2C Bridge Board Layout
Figure A-7. Top View
Figure A-8. Bottom View
A.2.1
Demo Board Layout
Figure A-9. Top View
62
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
A.3
Bill of Materials (BOM)
A.3.1
USB-I2C Bridge BOM
Item Qty Reference
1
1
C1
C2
Description
Manufacturer
Mfr Part Number
PCB
Cypress Semiconductor
PDC-9334
CAP CER .10UF 25V X7R 10% 0805
TDK
C2012X7R1E104K
CAP CER 1.0UF 10V 10% X7R 0805
Murata Electronics North
America
GRM21BR71A105KA01L
2
1
3
1
C3
CAP CER 2.2UF 16V Y5V 1206
Murata
GRM31MF51C225ZA01L
4
1
C4
CAP CER 10000PF 50V 10% X7R 1206
Murata
GRM319R71H103KA01D
5
2
C5, C6
CAP CERAMIC .01UF 100V X7R 0603
Kemet
C0603C103K1RACTU
6
1
R1
RES 52.3K OHM 1/10W 1% 0603 SMD
Yageo
RC0603FR-0752K3L
7
1
R2
RES 5.1K OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-075K1L
8
1
R3
RES 24.0K OHM 1/10W 1% 0603 SMD
Yageo
RC0603FR-0724KL
9
1
R4
RES 6.8K OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-076K8L
10
1
R5
RES 51K OHM 1/8W 5% 0805 SMD
Yageo
RC0805JR-0751KL
11
1
R6
RES 10K OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-0710KL
12
1
R7
RES 30.1K OHM 1/10W 1% 0603 SMD
Yageo
RC0603FR-0730K1L
13
1
R8
RES 51K OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-0751KL
14
2
R9, R10
RES 22 OHM 1/8W 5% 0805 SMD
Panasonic - ECG
ERJ-6GEYJ220V
15
2
R11, R12
RES 300 OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-07300RL
16
1
R13
RES 100K OHM 1/10W 5% 0603 SMD
Rohm
MCR03EZPJ104
17
2
R14, R15
RES 7.5K OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-077K5L
18
2
R16, R17
RES 30K OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-0730KL
19
3
R18, R19,
R20
RES 47 OHM 1/10W 5% 0603 SMD
Yageo
RC0603JR-0747RL
20
1
J1
CONN HEADER VERT 2POS .100 TIN
Molex/Waldom Electronics
22-28-4020
Corp
21
1
J2
CONN HEADER VERT 5POS .100 TIN
Molex/Waldom Electronics
22-28-4050
Corp
22
1
J3
CONN HEADER .100 SNGL STR 5POS
3M Electronics
929850-01-05-10
23
1
J4
Delphi Connection SysCONN USB RCPT MINI-B 5POS RT ANG
tems
24
2
F1, F2
POLYSWITCH 1.10A RESET FUSE SMD
Tyco Electronics/Raychem Circuit Protection
25
1
D1 *
LED 660NM RED WTR CLR 1206 SMD
Lumex Opto/Components
SML-LX1206SRC-TR
Inc
26
1
D2 *
LED 565NM WTR CLR GREEN 1206 SMD
Lumex Opto/Components
SML-LX1206GC-TR
Inc
15430262-110
MINISMDC110-2
27
2
D3, D4
Supressor 5V SMB package
Littelfuse Inc
SMBJ5.0CA
28
1
U1
IC LDO REG 1A SOT223-6 TPS73701
Texas Instruments
TPS73701DCQ
29
1
U2
CY8C24894
Cypress Semiconductor
CY8C24894-24LFXI
30
1
U4 *
IC Single USB Port TVS SOT-23-6
Texas Instruments
SN65220DBVT
31
1
U5
IC LVL XLTR LV 8MBPS 14-TSSOP
Maxim
MAX3378EEUD+
32
1
U6
TVS Array ESD 6 Input 8-SOIC
Littelfuse Inc
SP721ABG
33
2
* 000
RES 0.0 OHM 1/8W 5% 0805 SMD
Rohm
MCR10EZHJ000
34
1
* 000
RES 0.0 OHM 1/8W 5% 0603 SMD
Rohm
MCR03EZPJ000
35
1
J1 *
Shunt
3M
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CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B
63
A.3.2
Demo Board
Item Qty
64
Reference
Description
Manufacturer
PCB
Cypress Semiconductor
Mfr Part Number
PDC-9355
1
1
C1
CAP 100nF 25V CERAMIC X7R 0805
Panasonic - ECG
ECJ-2VB1E104K
2
1
R1
RES 75K OHM 1/8W 5% 0805 SMD
Yageo America
RC0805JR-0775KL
3
2
R2, R3
RES 1.0K OHM 1/8W 5% 0805 SMD
Yageo America
RC0805JR-071KL
4
1
D1
Visible Light Sensor
Microsemi Inc
LX1972IBC
5
2
D2, D3
LED RED CLEAR 0805 SMD
LITE-ON INC
LTST-C170CKT
6
1
U1
IC PSoC 21x23 8SOIC
Cypress Semiconductor
CY8C21123-24SXI
7
1
J1
CONN HEADER .100 SNGL STR 5POS
Samtec
TSW-105-07-T-S
CY3240 USB-I2C Bridge Guide, Doc. # 001-66660 Rev.*B