ESP8266 Community Forum

- Thu May 28, 2015 11:00 am #18741 Hey friends, got a weird one. I have a Pic24E which I connect to ESP-07. Connections are like this:

Code: Select allPIC:            ESP-07                    POWER
=============================================
UART TX -------- UART RX
UART RX -------- UART TX
GND -------------- GND
GPIO_PIC -- 10K -- CH_PD
                  GPIO15 ----- 15K ----- GND
                  GPIO2 ------ 15K ------ VCC
                  GPIO0 ------- 15K ------ VCC
                  GND ------------------ GND
                  VCC ------------------- VCC

Well here's the thing - when I pull GPIO_PIC up - I get a brown out reset (the system just sort of freezes in the middle of debugging. I can tell it's BOR by looking at the reset cause register). Why is this happening? Btw, I can wire up CH_PD via a pull up directly from VCC and that's fine.

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- Thu May 28, 2015 11:10 am #18742 Is the PIC running at 5V?

Why do you have 10k between the PIC and CH_PD? I would put a pull up on CH_PD and then a small value resistor between the PIC and CH_PD

- Thu May 28, 2015 11:23 am #18744 PIC's at 3.3V. The reason I put the 10K between the PIC and CH_PD is because I was thinking of pulling it up from the PIC. But I like your Idea, to instead do a pull down, better. I'll give it a shot and will let you know!

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- Fri May 29, 2015 10:37 pm #18916 Found my problem. My linear regulator is too weak. With PIC alone current draw is 9mA when esp8266 comes online (CH_PD up) that increases to 78mA. This increased draw causes the output voltage to sag from 3.26V to 2.88V which causes the debug tool (pickit3) to hang. Without the debug tool the system still runs, even at the low voltage. Crap. Now I need to find a new regulator

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