Search found 329 matches

by loboris
Wed Feb 21, 2018 9:06 am
Forum: Showcase
Topic: ESP32 TFT display library
Replies: 39
Views: 13262

Re: ESP32 TFT display library

I have some plans to update the library to be able to use 3-wire SPI displays, probably early next month. At the moment, it is not possible. thanks, but i really want to know how to do that? It shouldn't be difficult, I've did some tests and it should work. Basically, only the 9-bit spi transfer ha...
by loboris
Fri Feb 16, 2018 3:02 pm
Forum: ESP32 SDK
Topic: DMA example for UART communication for ESP32
Replies: 15
Views: 461

Re: DMA example for UART communication for ESP32

I don't think there is any need to use DMA with UART with your usage case. I'm only using the uart event task, similar to esp-idf/examples/peripherals/uart_events example. I've newer had any problems with it and response time is quite fast. At 128 byte packets every 100 ms you should have no problem...
by loboris
Thu Feb 15, 2018 6:12 pm
Forum: General Discussion
Topic: SPP profile in bluedroid missing?
Replies: 24
Views: 4619

Re: SPP profile in bluedroid missing?

Yes, it works fine.
by loboris
Thu Feb 15, 2018 8:58 am
Forum: General Discussion
Topic: Mosfet choice
Replies: 11
Views: 404

Re: Mosfet choice

Any of BSS123 will do. The schematics looks ok. I would suggest adding a 10 - 100 nF capacitor to the ADC. MCP1700 can provide max 250 mA, which may be insufficient for ESP32 when wifi is started. Holtek's HT7833 can provide 500 mA (quiescent current of 4 uA) and could be a better choice, but it has...
by loboris
Wed Feb 14, 2018 8:00 pm
Forum: ESP32 SDK
Topic: Need help to compress files into ESP32
Replies: 4
Views: 168

Re: Need help to compress files into ESP32

As far as I know, there is no folder compression support or library for ESP32. You could use zlib library to compress the files. Here is the link to the zlib component I'm using with only the files needed. There is no function in it to compress the directory, you will need to create your own functio...
by loboris
Wed Feb 14, 2018 6:31 pm
Forum: General Discussion
Topic: Mosfet choice
Replies: 11
Views: 404

Re: Mosfet choice

R9 is grounded to pull T2 gate low in case GPIO is floating. There is no need for serial resistor to the MOSFET gate (T2)! GPIO has to be configured as output. You can use any P MOSFET with similar characteristics, the RDS will have practically no influence on 2x 10K voltage divider. NDS356 has RDS ...
by loboris
Wed Feb 14, 2018 4:16 pm
Forum: General Discussion
Topic: Mosfet choice
Replies: 11
Views: 404

Re: Mosfet choice

@Azaelyus

none -> far less than 1 uA.
It should work with any voltage (on VBAT) up to 17V.

I've used this circuit to power the GSM module from LiPo battery, there was no measurable current when switched off (GPIO=0V).
by loboris
Wed Feb 14, 2018 8:43 am
Forum: Showcase
Topic: ESP32 TFT display library
Replies: 39
Views: 13262

Re: ESP32 TFT display library

I have some plans to update the library to be able to use 3-wire SPI displays, probably early next month.
At the moment, it is not possible.
by loboris
Wed Feb 14, 2018 8:34 am
Forum: General Discussion
Topic: How to override or detect SNTP_SET_SYSTEM_TIME_US?
Replies: 2
Views: 126

Re: How to override or detect SNTP_SET_SYSTEM_TIME_US?

I've needed the same thing and ended up adding the global variable sntp_is_synced which is set to true before calling SNTP_SET_SYSTEM_TIME_US in "sntp.c".
Not a very elegant solution because I've modified the file in the esp-idf, but it works fine.
by loboris
Tue Feb 13, 2018 11:22 pm
Forum: General Discussion
Topic: Mosfet choice
Replies: 11
Views: 404

Re: MOSFET CHOICE

I'm using NDS356 for P-MOS and you can replace BC547 with N-MOS. This is the schematics I'm using for years. Current drain is none when GPIO is low, setting GPIO to high opens the P-MOS. VBAT can be up to 18V, select the R10/R11 to get the desired voltage. You can use VPP to power some device (up to...

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