Search found 43 matches

by .rpv
Wed Jan 24, 2024 3:03 am
Forum: Projects
Topic: STM32F103C8T6 custom board download issue
Replies: 1
Views: 15177

Re: STM32F103C8T6 custom board download issue

Don't remember if serial does verification but upload by stlink does verification, so if you don't got any error on the stlink upload everything was right with the MCU, so the problem is somewhere else, without posting an schematic are just guesses:

- Boot pins is it configured right?... to boot ...
by .rpv
Wed Sep 15, 2021 9:17 am
Forum: Off topic
Topic: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets
Replies: 19
Views: 15162

Re: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets


@.rpv thanks!

ok i'd need to fix up my blue pill 'oscilloscope' & get that 74HCTxx (on the way) :mrgreen:

but SN74LVC1G17 seemed the best of them all.
this and the 74HCTxx series are hcmos devices,
https://www.ti.com/lit/pdf/scla007
so I'd guess it kind of says that hcmos devices are after all ...
by .rpv
Tue Aug 24, 2021 12:08 am
Forum: Off topic
Topic: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets
Replies: 19
Views: 15162

Re: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets

So I was curious and I tried:

Channel 1 (yellow) it's the DUT output, Channel 2 (green) it's the fungen, the VIN on the DUT was 5V.

LM321 with no load:

lm321_noload.png

LM321 with 1nf capacitor as load (barely any difference):

lm321_1nf.png

For comparison, SN74LVC1G17 with 1nf cap as load ...
by .rpv
Mon Aug 23, 2021 10:29 pm
Forum: Off topic
Topic: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets
Replies: 19
Views: 15162

Re: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets

The bed mosfet should be the most required to do an pwm level-up, but also it's really slow (~10hz), probably you can use an lm321/lm358/lm324 as comparator, for the heaters and fans the easiest way should be changing the mosfets:

-for the heater(s) the IRLZ44N works fine with 3v3
-on fans use the ...
by .rpv
Sun Aug 22, 2021 11:59 pm
Forum: General discussion
Topic: STM32F103C8T6 problem with EEPPROM..
Replies: 15
Views: 12485

Re: STM32F103C8T6 problem with EEPPROM..

Ok, first, in my experience using unsigned long it's problematic if you don't specify literally on each mention/operation

Something like this should work:

unsigned long x=1000000;

setup(){
//...//
Serial.print(x);
}

But I'll expect funny things on this:

unsigned long x;

setup(){
//...//
x ...
by .rpv
Sun Aug 22, 2021 11:32 pm
Forum: Off topic
Topic: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets
Replies: 19
Views: 15162

Re: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets

One project that I got for about 2 years it's to make a 3d printer controller :lol:

I just collected a few parts but still haven't started yet ;)

74HC125 (quad) (untested)
https://www.aliexpress.com/item/32344341714.html

SN74HC125 (single) (I tested this part and works nice)
https://www ...
by .rpv
Sun Aug 22, 2021 9:55 am
Forum: General discussion
Topic: STM32F103C8T6 problem with EEPPROM..
Replies: 15
Views: 12485

Re: STM32F103C8T6 problem with EEPPROM..

You aren't posting any info or the actual errors that you're getting, but it seems that you aren't selecting the right board on the arduino ide or you core installation on the IDE may be incomplete.

The eeprom libraries are supplied on both STCore and on libmaple-type cores and neither should give ...
by .rpv
Sun Aug 22, 2021 9:51 am
Forum: Off topic
Topic: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets
Replies: 19
Views: 15162

Re: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets

Is your board like this:

https://raw.githubusercontent.com/bigtreetech/ramps-1.6/master/Ramps1.6/hardware/R6%2B-SCH.pdf

?

if so you can connect vcc to 3v3, all but the mosfet should work with 3v3 as VCC, you just need to level up the PWM to 5v, this also because the thermistors are connected to ...
by .rpv
Sat Aug 21, 2021 10:24 pm
Forum: General discussion
Topic: STM32F103C8T6 problem with EEPPROM..
Replies: 15
Views: 12485

Re: STM32F103C8T6 problem with EEPPROM..

Hi, are you using an external eeprom?, if you're using the internal flash as eeprom and if you're using the stcore you can use the standar eeprom library, no need to use external libraries, you can use the standard API:

https://www.arduino.cc/en/Reference/EEPROM

The libmaple variants also support ...
by .rpv
Sat Aug 21, 2021 6:12 pm
Forum: Off topic
Topic: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets
Replies: 19
Views: 15162

Re: 74HC(T)245 interfacing 5v cifcuits e.g. driving 5v logic level mosfets

ag123 are you using a ramps or are designing your own board?

Here it's the ST STEVAL-3DP001V1 3d printer controller:

https://www.st.com/en/evaluation-tools/steval-3dp001v1.html#documentation

on the tab documentation, Product Specifications pdf they included the schematic.


The bigtreetech brand ...

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