PSoC™ 5, 3 & 1 Forum Discussions

The Cypress website has over 50 application notes (AN) on PSoC1 covering a wide range of topics. We have taken several steps to enable you to quickly ... Show More

By Anonymous

Nov 10, 2011

302

PSoC™ 5, 3 & 1

PSoC1 Application Note Finder

The Cypress website has over 50 application notes (AN) on PSoC1 covering a wide range of topics. We have taken several steps to enable you to quickly ... Show More

By Anonymous

Nov 9, 2011

380

PSoC™ 5, 3 & 1

PSoC3/PSoC5 bootloader

Have you ever tried upgrading the firmware on your mobile phone, MP3 player, camera or tablet? The seamless process by which you can do this is f... Show More

Have you ever tried upgrading the firmware on your mobile phone, MP3 player, camera or tablet? The seamless process by which you can do this is facilitated by a bootloader, eliminating the need for an external programmer or disassembling the product. A bootloader is an absolute necessity in consumer technology today, to keep pace with rapidly evolving competition and keep customers excited about your product everyday! For embedded system designers, it also opens up a door to fix bugs in a shipped product.

Figure below shows a typical bootloader system in PSoC3/PSoC5. A PSoC3/PSoC5 bootloader allows you to reconfigure the on-chip hardware as well as to upgrade the application firmware. The devices support I2C and USB as standard communication protocols for bootloading.

A typical PSoC 3/PSoC 5 bootloader system has the following elements:

Bootloader host: It can be a PC or an embedded host capable of communicating with the target device.
Bootloader: This is a piece of code that resides in the target device and capable of communicating with the host, re-flashing the device and handing control to the application. The bootloader is usually factory programmed onto the device.
Bootloadable project: This is the actual application in the target device. It can be changed using the bootloader.

To modify or upgrade the bootloadable project in the device, the host sends the new project and data over a communication interface. The bootloader receives this new project code and data, and writes it to the bootloadable flash. It passes control to the bootloadable project once the new project/application is successfully bootloaded.

Here are some facts that you may want to know about PSoC3/PSoC5 bootloaders:

PSoC3/PSoC5 bootloader allows you to reconfigure both hardware resources as well as firmware.
The bootloader is created as a separate project. The bootloadable project is linked to the bootloader project using the dependency option in PSoC Creator IDE.
You can build your own custom communication interface for bootloading.
A typical PSoC3 I2C bootloader project only consumes 7 kB of flash.
It is possible to protect the security settings of the bootloader flash to prevent any accidental rewrites to the bootloader itself.
PSoC3/PSoC5 bootloaders are fail-safe. The bootloadable project checksum is validated during power-up. When the checksum is invalid, the bootloader will wait for a valid image to be bootloaded. This is useful in situations where power fails during bootloading.

Are you looking for a fast and easy way to add an I2C bootloader to your PSoC 3 or PSoC 5 project? Please refer application note AN60317 ! Please let us know your feedback in the comments section below.

Show Less

By Anonymous

Nov 10, 2011

575

PSoC™ 5, 3 & 1

Serial Ports are so 1990!

USB devices are so common today and it has pretty much become the standard of the day for data transfers and for many of the common applications. Ther... Show More

By Anonymous

Nov 10, 2011

270

PSoC™ 5, 3 & 1

Serial Ports are so 1990!

Let’s face it, serial ports on designs are fading away which is causing many embedded developers headaches when they want to add a reliable... Show More

Let’s face it, serial ports on designs are fading away which is causing many embedded developers headaches when they want to add a reliable method to transfer data from the PSoC to the PC. Many people shy away from USB because it appears intimidating. In reality, once some basics of USB are understood, it really isn’t that difficult to understand and use.

In a nutshell, a USB system consists of a host, which is typically a personal computer (PC) and multiple peripheral devices connected through a tiered-star topology. This topology may also include hubs that allow additional connection points to the USB system. The host itself contains two components, the host controller and the root hub. The host controller is a hardware chipset with a software driver layer that is responsible for the following tasks:

Detect attachment and removal of USB devices
Manage data flow between host and devices
Provide and manage power to attached devices
Monitor activity on the bus

At least one host controller is present in a host and it is possible to have more than one host controller. Each controller allows the connection of up to 127 devices with the use of external USB hubs. The root hub is an internal hub that connects to the host controller(s) and acts as the first interface layer to the USB in a system. Currently on your PC, there are multiple USB ports. These ports are part of the root hub in your PC. For simplicity, look at the root hub and host controller from the abstract view of a “black box” that we call the host.

USB devices consist of one or more device functions, such as a mouse, keyboard, or audio device for example. Each device is given an address by the host, which is used in the data communication between that device and the host. USB device communication is done though pipes. These pipes are a connection pathway from the host controller to an addressable buffer called an endpoint. An endpoint stores received data from the host and holds data that is waiting to transmit to the host. A USB device can have multiple endpoints and each endpoint has a pipe associated with it.

There are two types of pipes in a USB system, control pipes and data pipes. The USB specification defines four different data transfer types. Which pipe is used depends on the data transfer type.

Control Transfers Used for sending commands to the device, make inquiries, and configure the device. This transfer uses the control pipe.
Interrupt Transfers Used for sending small amounts of bursty data that requires a guaranteed minimum latency. This transfer uses a data pipe.
Bulk Transfers Used for large data transfers that use all available USB bandwidth with no guarantee on transfer speed or latency. This transfer uses a data pipe.
Isochronous Transfers Used for data that requires a guaranteed data delivery rate. Isochronous transfers are capable of this guaranteed delivery time due to their guaranteed latency, guaranteed bus bandwidth, and lack of error correction. Without the error correction, there is no halt in transmission while packets containing errors are resent. This transfer uses a data pipe.

Every device has a control pipe and it is through this pipe that control transfers to send and receive messages from the device are performed. Optionally, a device may have data pipes for transferring data through interrupt, bulk, or isochronous transfers. The control pipe is the only bidirectional pipe in the USB system. All the data pipes are unidirectional. Each endpoint is accessed with a device address (assigned by the host) and an endpoint number (assigned by the device). When information is sent to the device the device address and endpoint number are identified with a token packet. The host initiates this token packet before a data transaction.

When a USB device is first connected to a host, the USB enumeration process is initiated. Enumeration is the process of exchanging information between the device and the host that includes learning about the device. Additionally, enumeration includes assigning an address to the device, reading descriptors (which are data structures that provide information about the device), and assigning and loading a device driver. This entire process can occur in seconds. Once this process is complete, the device is ready to transfer data to the host. Two files are affiliated with enumeration and the loading of a driver. These files are the INF and SYS file, and they exist on the host side.

After a device has been enumerated, the host directs all traffic flow to the devices on the bus. When implementing USB in a PSoC, all you need to do is configure the USB Full Speed component as described in the component data sheet, and then use the Cypress provided API’s to load data into an IN endpoint and take data out of an OUT endpoint.

Since the host manages the traffic, it will handle everything else in conjunction with the dedicated USB hardware in the PSoC. Most of the intimidating factors regarding USB are on the host side, and in most USB applications users will not need to worry about the host side of things. That aspect is reserved for the most advanced of USB applications.

All the user needs to do is determine what data they want to transfer between the PSoC and the PC, and what type of transfer they want to initiate (Control/Interrupt/Bulk/Isochronous).

Once you get a USB project working, you will wonder why you ever used serial ports in the first place.

For more information about USB pertaining to the following topics, along with links to other Cypress PSoC USB application notes refer to AN57294- USB 101: An Introduction to Universal Serial Bus 2.0.

USB History
USB Architecture
USB Physical Interface
USB Speeds
USB Power
USB Endpoints
USB Communication Protocol
USB Descriptors
USB Class Devices
USB Enumeration and Configuration Process
USB Compliance and Windows Logo Testing

Show Less

By Anonymous

Nov 10, 2011

319

PSoC™ 5, 3 & 1

PSoC1 Application Note Finder

PSoC1 Application Note Finder The Cypress website has over 50 application notes (AN) on PSoC1 covering a wide range of topics. We have... Show More

By Anonymous

Nov 9, 2011

204

PSoC™ 5, 3 & 1

FreeRTOS PSoc5

Hi I'm quit new with PSoc and I want to install FreeRTOS on PSOC5 So when I wnat to open the workspace from "FreeRTOS/Demo/CORTEX_CY8C5588_PSoC_Cre... Show More

By Anonymous

Nov 9, 2011

334

PSoC™ 5, 3 & 1

How to use an CY3212 CapSense EvalBoard with PSoC Designer V5.0

Hi, I tried to use an (older ) CY3212-CapSense RevC Board from 2006 together with PSoC Designer 5 . The on board chip is a CY8C21001-24P... Show More

By DrBu_265381

May 4, 2010

701

PSoC™ 5, 3 & 1

i2c read

I am using the cy8c20546A as an i2c slave using the ezi2c module. When the master writes into the slave the ezi2c_anyactivity flag is getting set but ... Show More

By Anonymous

Nov 1, 2011

303

PSoC™ 5, 3 & 1

Mixer Component Variable Frequency LO

Hie, I am trying to use the mixer component in PSoC Creator for a project where I need the mixer to have its Local Oscillator sweeping across a wid... Show More

By Anonymous

Oct 25, 2011

614