Some ref material -
http://www.cypress.com/?rID=57561 AN73503 - USB HID Bootloader for PSoC® 3 and PSoC 5LP
http://www.cypress.com/?rID=50230 AN68272 - PSoC® 3, PSoC 4 and PSoC 5LP UART Bootloader
http://www.cypress.com/?rID=41002 AN60317 - PSoC® 3 and PSoC 5LP I2C Bootloader
http://www.cypress.com/?rID=78703 AN84401 - PSoC® 3 and PSoC 5LP SPI Bootloader
"Memory issues due to some reason" makes me shiver. Wouldn't it be safer to evolve the reason for issues to avoid the cause (and not the symptom)
Bob update process that they have written is very memory consuming which we dont want to use.
So we decided to go for creating our own bootloader component. is it possible to do it using cypress creator ide?
If yes then can you please provide some inputs to me? from where to start?
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Memory consuming Bootloader? To implement the very basic bootloader functions some flash will be needed, no matter, but I question whether you will save a reasonable amount of rom-bytes by writing the code yourself.
Concerning ram: when the bootloader passes contol to the bootloaded all ram in use will be freed, so that will not be an issue.
A Bootloader is program as any other one. So it should be not to complicated to wrote one by yourself. I would start by looking at the bootloader component data sheet.
Basically you just need:
- a toogle to decide when to start the application and when to bootload (e.g. a pin)
- a communication system (for downloading the new application)
- a flash write logic to store the new application in memory
- and a PC application for sending the new application to the PSoC
The Bootloadable application then gets a reference to your bootloader, so it knows about its size (for memory placement).
The bootloader component datasheets also has a description of the communication protocol, so you might reuse that.
Btw: the PSoC3 bootloader is just 2k in size, and needs 4 bytes of sRAM. Are you sure you will be significantly better than that? Its the communication part which needs more space (the datasheets says for I2C one needs additional 4k flash and 1.5k RAM), and you won't probably save much there...
We have tdecide to go for creating our own simple bootloader for psoc 3 device.
Can you please give me some inputs how to design using creator ide.
Read the bootloader component data sheet. It explains how such a component works. I think you also should read the TRM, to learn about writing to flash memory. Anything else is just 'normal' programming, so there is nothing special to point you to.
But I think you still should check wheter its possible to go with the existing bootloader. You still didn't state what your actual problem is...
actually we have a specific requirement about how update the application software in the field which is not available in the current bootloader. we can not use updating facility given by current bootloader.
is it possible to develop simple bootloader component from scratch using creator ide?
if yes can you please give us some inputs of how to start?
Oh, you didn't mention such specific requirements before. You said you had 'memory issues'... Maybe you can ask your Cypress representative whether these requirements could be implement in the existing component in one of the next updates?
Yes, you can implement a bootloader in PSoC Creator. I guess its not that complicated. And I already gave you all the pointers you should need (twice already...).
I started referring TRM document.
but i am not getting how to access SFR's when creating library project for bootloader component.
As I am new to PSoC devices i am not getting things clearly.
Can you please guide me into this?
is there any sample source code with you which is creating compoent using SFR's?
SFRs? Do you mean 'special function registers'? What do you want to do with them? (I guess you should read the PSoC3 TRM, and the registers TRM for more info on that).
There is no need, I think, to create a new component or a library for the bootloader. Just develop it as a normal application - its just one that reads stuff over UART / USB / whatever and stores it into flash memory and is able to run this code.
In your bootloadable application you then reference the hex file created for your bootloader app, so your real app can be put into the proper memory location by the linker.
I am trying to create CAN bootloder can u please help me.
Please don't hijack existing threads with different topics with your new question. Please open a new topic if you have a new questions. That way you will get better answers, since it gets more visbility.
(and btw. - I answered to your other question)