ESP32 Forum

Posted: **Sun Nov 06, 2016 9:33 pm**

Sad truth or I have a wrong baudrate feeling.

i am woundering in test with DevKitC and Silabs CP2102,
i get allways fatal error with 2 Mbit

Code: Select all

Flashing binaries to serial port COM27 (app at offset 0x10000)...
esptool.py v2.0-dev
Connecting...
Uploading stub...
Running stub...
Stub running...
Changing baud rate to 2000000
Changed.
Attaching SPI flash...

A fatal error occurred: Timed out waiting for packet header
make: *** [c:/sdk32/esp-idf/components/esptool_py/Makefile.projbuild:31: flash] Error 2

after checked datasheet, there saw sad truth

S. 15

CP2102-9.pdf: (1.92 MiB) Downloaded 811 times

Table 12. Data Formats and Baud Rates
limit on 921600..and only fixed rates:

300, 600, 1200, 1800, 2400, 4000, 4800, 7200, 9600, 14400, 16000, 19200, 28800, 38400,
51200, 56000, 57600, 64000, 76800, 115200,
128000, 153600, 230400, 250000, 256000,
460800, 500000, 576000, 921600

please say me, i took the wrong datasheet and point me in ther right or
say me, "you must live with 921600"

who has select Silabs on DevKitC - why not FTDI

best wishes
rudi

btw:

FTDI 231XQ was used on NANO32 and support flexible range 183.1 baud to 3,000,000 baud.
The FT231X supports all standard baud rates and non standard baud rates from 183 Baud up to 3 Mbaud

S. 14
http://cdn.sparkfun.com/datasheets/Comp ... FT231X.pdf

DS_FT231X.pdf: (825.23 KiB) Downloaded 801 times

Baud Rate Generator
–
The Baud Rate Generator provides a 16x clock input to the UART Controller
from the 48MHz reference clock. It consists of a 14 bit prescalar
and 3 register bits which provide fine tuning of the baud rate
(used to divide by a number plus a fraction or “subinteger”). This determines the
baud rate of the UART, which is programmable from 183 baud to 3 Mbaud.
The FT231X supports all standard baud rates and non
- standard baud rates from 183 Baud up to 3 Mbaud.

Achievable non standard baud rates are calculated as follows
–
Baud Rate = 3000000 / (n + x)
where ‘n’ can be any integer between 2 and 16,384 ( = 214) and ‘x’ can be a subinteger of the value 0,
0.125, 0.25, 0.375, 0.5, 0.625, 0.75, or 0.875. When n = 1, x= 0,
i.e. baud rate divisors with values between 1 and 2 are not possible.
This gives achievable baud rates in the range 183.1 baud to 3,000,000 baud. When a non
standard baud rate is required simply pass the required baud rate value to the driver as normal, and the FTDI driver will
calculate the required divisor, and set the baud rate. See FTDI application note
AN232B05 on the FTDI website ( http://www.ftdichip.com ) for more details.

3.000 000 Baud
done!

: FTDI_NANO32.png (46.14 KiB) Viewed 14044 times

Posted: **Sun Nov 06, 2016 11:11 pm**

The datasheet is correct. I believe the CP2012 can support up to 1Mbit, but on Windows the driver may only support max 921600 without an additional "baud rate aliasing" hack. The Linux cp201x kernel driver appears to support 2Mbit, but it's never worked for me either.

For flashing large amounts of data the bottleneck is currently decompression speed (note the 356kbit/sec for the larger image in the screenshot). Although I agree it'd be nice to have higher UART speeds on the dev boards.

DevKitJ (aka ESP-WROVER) has an integrated FT2232H for both serial and JTAG. This can theoretically transfer UART data at 12Mbit, although I don't know if this is supported on DevKitJ.

Posted: **Sun Nov 06, 2016 11:49 pm**

ESP_Angus wrote:The datasheet is correct. I believe the CP2012 can support up to 1Mbit, but on Windows the driver may only support max 921600 without an additional "baud rate aliasing" hack. The Linux cp201x kernel driver appears to support 2Mbit, but it's never worked for me either.

Thanks Angus,

where is the difference on 921600 to 1 MBit

yes - have try the things to go faster with linux kernel too, but the hardware is limited.

ESP_Angus wrote: For flashing large amounts of data the bottleneck is currently decompression speed (note the 356kbit/sec for the larger image in the screenshot). Although I agree it'd be nice to have higher UART speeds on the dev boards.

DevKitJ (aka ESP-WROVER) has an integrated FT2232H for both serial and JTAG. This can theoretically transfer UART data at 12Mbit, although I don't know if this is supported on DevKitJ.

yes - i got a parcel last days from espressif - i hoped sooooooooo for the RED DevKit J ( aka ESP-WROVER ) ...

i get the newest DevKitC V2 .. with Cased WROOM32.. but i test just in time - i think this is monday modul,
after flashing, the boot is in a while.. i must try again next days.

so i think we must live with 921600 with this Silabs

best wishes
rudi

btw ..
olimex DevKitC V2...
i see 'K' on trace ( PCB antenna ) on olimex - same in ESP-32S from AI Thinker
and no Case on the Modul

: DevKitC_V2.jpg (210.3 KiB) Viewed 14035 times

and the newest from espressif V2 i get .. change only Cased or more? do you know? -

: x1.jpg (118.31 KiB) Viewed 14035 times

Posted: **Mon Nov 07, 2016 12:05 am**

rudi ;-) wrote: and the newest from espressif V2 i get .. change only Cased or more? do you know? -

I believe the only difference is the RF shielding can on the module.

Angus

Posted: **Tue Nov 08, 2016 11:45 pm**

ESP_Angus wrote:The datasheet is correct. I believe the CP2012 can support up to 1Mbit, but on Windows the driver may only support max 921600 without an additional "baud rate aliasing" hack. The Linux cp201x kernel driver appears to support 2Mbit, but it's never worked for me either.

For flashing large amounts of data the bottleneck is currently decompression speed (note the 356kbit/sec for the larger image in the screenshot). Although I agree it'd be nice to have higher UART speeds on the dev boards.

Hi Angus,

https://twitter.com/welectronic/status/ ... 2305934336

Silabs CP2102 N

Site 15:

cp2102n-datasheet.pdf: (925.96 KiB) Downloaded 813 times

did the trick on watterott's new ESP32 Breakout

: Cp2102N_ESP32_breakout_Test_8_Nov_2016.png (240.61 KiB) Viewed 13940 times

we have :
300, 600, 1200, 1800, 2400, 4000, 4800, 7200, 9600, 14400,
16000, 19200, 28800, 38400, 51200, 56000, 57600, 64000,
76800, 115200, 128000, 153600, 230400, 250000, 256000,
460800, 500000, 576000, 921600, 1000000, 1200000, 1500000,
2000000, 3000000

The baud rate generator is very flexible, allowing the user to request any baud rate in the range from 300 baud to 3 Mbaud.

ESP32 Forum

Silabs CP2102 on DevKitC V2 dont support Baud more as 921600 ?

Silabs CP2102 on DevKitC V2 dont support Baud more as 921600 ?

Re: Silaps CP2102 on DevKitC V2 dont support Baud more as 921600 ?

Re: Silabs CP2102 on DevKitC V2 dont support Baud more as 921600 ?

Re: Silabs CP2102 on DevKitC V2 dont support Baud more as 921600 ?

Re: Silaps CP2102 on DevKitC V2 dont support Baud more as 921600 ?