Trantuete

Ahh....forget what I said about jitter...it's allright. I checked that again and I've got jitter of +/-2 and a very few times +/-3. I think that's OK. Maybe I'll try other pot values and see if that makes any difference. Thank you very much for support...µCApps is a great project! I'm learning so much working on my own project. And I realize how much work you put in here to establish this awesome platform. I really appreciate your work. If I ever get to finish my project, I will post some pictures or a video here. It's kind of an alternative use for MIOS. But since it's my very first MIOS project, and I'm just learning to program in C, it may still take a while.

Hi, hope you had a nice and long weekend...well at least here in Germany. Little update: Switching to push-pull mode did not solve the problem. The signals still looked weird although now with a level of around 3 V. Next thing I tried, was to change the SPI peripheral that was used to J16 instead of J19 (changing the "#define AINSER_SPI" hook in ainser.h to 0) et voilá, it works. AINSER_jitter_mon now outputs jitter values of up to 7. Not perfect, but I'm happy for the moment. Looks like my PORTB or at least the outout transistors are damaged, for what reason ever. My J5 input pins connected to PORTB however do work. So now 'm gonna use J16 for AINSER. Any idea on how to improve jittering? I'm supplying my core with batteries, a standard 3.3V Regulator and a low drop 5 V Regulator. So ripple should not be the issue... Maybe the value of my test potentiometer is too high (470k) so it introduces measurable resistive noise. On the other hand it's fed through a low-pass filter with a cut-off-frequency as low as a handfull of Hz. Any idea is welcome... Thanks very much for the support so far...

Wow, thanks for being so kind to measure the signal on your core. And so quickly... appreciate that. I should mention that I'm using the STM32 Core. So there's no 74HCT541. The MCP3208 is controlled by the STM directly via pull up resistors on the SC, SO and RC lines. If I disconnect the MCP3208 so that I can measure the signal directly, it looks the same as before, so it seems to be a problem of the µC. I checked all the Vdd voltages on the stm32. They're all at 3.3V so everything is OK here. I have no idea what else could be the problem... :no: Maybe I should try and configure the outputs in push/pull mode and see if I get the right signals. The MCP3208 should be able to handle 3.3V signals, right? Best regards, Simon

Hi again, I just scoped the signals between µC and MCP3208 and they look a bit strange I think. I attached two scopes of the Clock Signal, one with a Time base of 250 µs and the other with 1 µs. Is that how the Clock is supposed to look? I rather thought of a square signal... I used 3,3V --> 5V levelshifting and the Signal doesn't even reach 4 V. The other Signals CS and Din also don't reach 5V. Regards, Simon

Thanks for quick answer... First of all I don't have any LEDs connected to the module. The uC Link LED is controlled by the 74HC595 and since I don't use multiplexers, I also don't have the 595... I'm supplying both the Vdd and the Vref from one 5V regulator, only the 10 Ohms resistor between them. The voltages are OK at 4.97 V. The Potentiometer is connected to CH7 (mirrored as you said) of the MCP3208...and that corresponds with what I see in MIOS Studio: I only see values for the first eight pins of module 1. If I type check_mux 2...8 I see only "--". So I guess the communication is running. Only the values don't correspond to my Analog Input Voltage, which is adjustable between 0 V and Vref. This is the display of MIOS Studio (Attachment) It looks like the input was floating but always at the top of the range. And as I said, changes on the analog input voltage don't cause any changes. I tried other channels of the MCP3208....same thing... Maybe the MCP 3208 is defective, also it's straight out of the box... The AINSER8 module sounds good, and looking at the schematics,... that's exactly what I have here....I simply left out the LED...everything else is identical. Guess I'm gonna do a little more research or simply buy a new MCP3208 .... :pinch: Thanks for the help... MIOSStudio.bmp

Hi Forum, I have a problem with the AINSER64 module. Well, actually it's not the complete module, but only the MCP3208 I am using, because I need only one single ADC channel with the low jitter values of the MCP. So I simply used one single analog input and clamped all other inputs to ground. No need for multiplexers and shift register. I used the ainser_jitter_mon application to test it and MIOS Studio only reports conversion values for module 1 and mux 1 on all eight channels of mux 1. So far so good,...., but: No matter what position my potentiometer is in, the values permanently are in the range of 3800 - 4095 with huge jitter values of 192 and more. The voltage on the analog input of the MCP does behave as intended when I move the potentiometer. But the ADC values don't. They stay at 3800+... I guess there's some communication error.... any idea someone? Thanks for help...

Wow, thanks...didn't see that...

Hi, quick question: I want to generate a fast and accurate PWM signal with the stm32 integrated PWM-mode of the general purpose timer. Right now the timer function of MIOS32 does not enable me to access this mode. How can that be done? So far, I know that the corresponding GPIO pin has to be configured in Alternate Function mode, to be able to connect to on chip peripheral signal sources like the PWM Generator. I added this mode to the pin modes in mios32_board.c and the correspondig header file. But I can't seem to figure out, how to initialize the timer for that mode. :no: Help please? Regards

Works! Thank You... Regards Simon

Thanks for your help so far. I'll be back for sure if something else doesn't work.... PS: did you know, that Arnold Schwarzenegger at first did not want to say that: "I'll be back"? He thought it sounded too feminine....little side information....unnecessary but funny...

O.K. I will get myself a 12 MHz crystal and try. The µC might accept 8 MHz crystals but I guess the software configures it for 12. I'm not that much of a software shark, you know....

Hi, thanks for the quick reply. The datasheet of the STM32 says: "The high-speed external (HSE) clock can be supplied with a 4 to 16 MHz crystal/ceramic resonator oscillator." So this should be no problem. Unfortunately I've got no 12MHz Crystal at hand to test it. Regards

Hi, my first post here in the forum...let's start with a problem. If found similar topics in the forum, but my issue is a bit different. I finished my STM32 Core Module with my own PCB design. PCB is OK, everything I tested seems to work so far. BUT, when connecting it via USB to my WinXP computer, it's not recognized. I get the message that the device connected to the usb port was not installed properly and may not work. Then it's listed as "unknown device". I tried it in Bootloader Hold Mode, but same problem. I'm usig a STM32RCT6 runnig with a 8 MHz crystal. I flashed it via SWD with a STLink device. Is there anything I have to change in the software or configuration? Any ideas? I appreciate every reply regards