PSoC™ 5, 3 & 1 Forum Discussions

Hi all,

how do I get printf() working with newlib-nano and a UART / USBUART

I am useing Creator 3.3 with the ARM GCC 4.9-2015-q1-update

first I've read various posts in this forum regarding formatted output via UART / USBUART and the use of sprintf() vs. printf(), for instance this one here: http://www.cypress.com/forum/psoc-5-device-programming/how-do-i-do-printf-function-psoc5?source=search&keywords=newlib-nano&cat=community 

When linking with newlib (Use newlib-nano = False) it works fine and the _write() stub functions I provide obviously overrides the weak implementation in newlib. In other words: printf() writes output to my USBUART / Putty

However, when linking with newlib-nano (Use newlib-nano = True) the _write() function in my stubs.c file is never called. When doing assembly stepping,  I can dig deeper in the call hierarchy but never end in a function _write() as in the newlib case.

Now my questions:

1) how is "stubbing" supposed to work on newlib-nano?

2) anybody got this working?

Note that I know the workarounds / alternatives with sprintf() and then streaming the char arr to an output, that's not the point here.

Just thought it would be nice to have something tiny working the "usual C way"

Regards,

Christof

Hi, While trying to test hibernation of Psoc5LP (cy8c5868axi-032LP) to minimize power consumption I have lost the device. This means J-LINK is unable to detect the device over SWD. I configured the SWD pins as GPIO as suggested by power management in order to obtain lowest possible power consumption. The SWD port shoult be possible waken up after reset and the GPIO pins will be SWD again. But I fail to access the SWD port with J-LINK programmer.

I wonder if there is some trick that the programmer must do and the J-LINK does not do that. Any experience?

I attached the project that will brick the device for me in order you can see maybe there is something else wrong too. I have carefully verified the bricking flag of firmware protection.

Hello,

Questions: 

- What could cause the PSOC5 to heat up and cause the 3.3v bus to modulate a square wave?

- Should I power the PSOC5 from whatever voltage Vdda has running to it?

Background:

I'm working on a custom board that uses a PSOC5 68 pin package. The design has the PSOC5 running of 3.3V, Vdda at 5v and most of the other Vddio pins are set to 3,3v. If I power the PSOC5 from the miniprog, it shows up in psoc creator and there is no smoke. If I then plug my benchtop power supply in and then reconnect the miniprog, the psoc doesn't shows up. If I then disconnect the benchtop supply and hook up the miniprog like in the first case, the psoc never shows up. When I solder up just the power supply part of my circuit, the signal looks good with no ripple. The rise time is about 0.055V/us. 

To continue with the oddness, if I power a complete board (power circuit + psoc5) from the bench, there is a square wave on my 3.3v lines and the psoc5 gets to hot to touch. 

I'm running out of boards to solder up so I thought I'd get a few opinion on this before burning more chips up.

Hi, 

is it possible to design a band stop filter with 50 hz on psoc using a filter block?

I tried but in pratical didn't work...

Thanks.

Regards,

Romil A.