Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

User avatar
By EadF
#11314 Just during the bootup process: https://github.com/esp8266/esp8266-wiki ... boot-modes (MTDO=GPIO15)

After that they don't need to be pulled. Tricky bit is to know when the esp is rebooting, so a permenent resistor is usually the easiest solution.

GPIO0 can be left floating and it will boot in "Boot from SPI Flash" mode in 99% of the time, but GPIO15 really needs a pull (in my experience)
User avatar
By zhivko
#11364
EadF wrote:Just during the bootup process: https://github.com/esp8266/esp8266-wiki ... boot-modes (MTDO=GPIO15)

After that they don't need to be pulled. Tricky bit is to know when the esp is rebooting, so a permenent resistor is usually the easiest solution.

GPIO0 can be left floating and it will boot in "Boot from SPI Flash" mode in 99% of the time, but GPIO15 really needs a pull (in my experience)

Permanent resistor to which pin? Is the schematics posted above OK or not?
User avatar
By mano1979
#11370 I am making adjustments to the pcb according to your comments. (Current design is probably not working)

The diode to gnd is reverse polarity protection.
if the power is connected the other way around, the diode will keep the current from flowing and destroy the module.

Updated board design coming later today.