UART Problem at boot time

[parmar7725274]

Hi all,

I have ESP 12q module and I have written my own firmware to send Sensor reading to server via TCP. The sensor module is connected througn UART ( using Tx and Rx pins ) and everything is working fine when I power on ESP module first and Sensor module after few seconds. But if I powered sensor module first and ESP module after few seconds then ESP module won't start and gives following prints in console.

0ÿLÿFatal exception 0(IllegalInstructionCause):
epc1=0x40240bfc, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
ò˜.Öò.¤„ÿ1ä)-ôÊÕ§ÈÙ…0ÿLÿFatal exception 0(IllegalInstructionCause):
epc1=0x40240bfc, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
ò˜.Öò.¤Î1ä)-ôÊÕ§ÈÙ…0ÿLÿFatal exception 0(IllegalInstructionCause):
epc1=0x40240bfc, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
òÃ.î².¤„ÿ1ä)-ôÊÕ§ÈÙ…0ÿLÿFatal exception 0(IllegalInstructionCause):
epc1=0x40240bfc, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
ò˜.Öò.¤„ÿ1ä)-ôŠj­ÈÙ…0ÿLÿFatal exception 0(IllegalInstructionCause):
epc1=0x40240bfc, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000

Please help !!

Thanks & Regards,
Prakash P.

[nitro.tm]

I found the same problem today. It seems related to the UART interrupt handler somehow. As soon as I send one character through the UART (from computer), it reboots and display this error (IllegalInstructionCause).

I have my own handler / uart setup. I tried to remove everything from the interrupt handler (no code at all) but it still has the same problem. Was working before sdk 1.5.0 update.