I am having trouble with a new board that has an ESP-12S module on it (ESP-8266 based). I'm having trouble finding any references to boot mode (3,0), and it is not a great search term.
I removed all the extra connections so all I have are:
RX/TX (confirmed correct RX to TX by seeing the boot message (included at the end of this post):
RTS: goes to ENA pin
CTS: goes to GPIO0
RESET pulled HIGH
GPIO2 pulled HIGH
GPIO15 grounded
All other pins unconnected; I raised the module up on a couple of layers of Kapton and only bridged those pins to the board or directly to wires from my USB to TTL serial adapter.
When I try to program, all I get is eternal intermittent flashing of the blue LED on the module.
Any ideas? I'm stumped as to where to go next.
--Andy
Boot message:
ets Jan 8 2013,rst cause:2, boot mode:(3,0)
load 0x40100000, len 1856, room 16
tail 0
chksum 0x63
load 0x3ffe8000, len 776, room 8
tail 0
chksum 0x02
load 0x3ffe8310, len 552, room 8
tail 0
chksum 0x79
csum 0x79
2nd boot version : 1.5
SPI Speed : 40MHz
SPI Mode : DIO
SPI Flash Size & Map: 32Mbit(512KB+512KB)
jump to run user1 @ 1000
rf cal sector: 1017
rf[112] : 00
rf[113] : 00
rf[114] : 01
SDK ver: 1.5.4.1(39cb9a32) compiled @ Jul 1 2016 20:04:35
phy ver: 972, pp ver: 10.1