picocom -b 115200 /dev/ttyUSB2 ets Jun 8 2016 00:22:57 rst:0x10 (RTCWDT_RTC_RESET),boot:0x33 (SPI_FAST_FLASH_BOOT) flash read err, 1000 Falling back to built-in command interpreter. OK >ets Jun 8 2016 00:22:57 rst:0x10 (RTCWDT_RTC_RESET),boot:0x33 (SPI_FAST_FLASH_BOOT) flash read err, 1000 Falling back to built-in command interpreter. OKIt does this in a loop until I hit return, then it stops at the ">" prompt waiting. You can get an informational greeting as follows:
>about ESP32 ROM Basic (c) 2016 Espressif Shanghai Derived from TinyBasic Plus by Mike Field and Scott Lawrence
strings esp32.bin | grep built Falling back to built-in command interpreter.Very likely TinyBasic uses some kind of compression or scheme more compact than ascii to represent characters. The above string is at address 0x4006eeef, as follows:
4006eee0 2025 752c 2025 7520 6473 2025 700a 0046 %u, %u ds %p F 4006eef0 616c 6c69 6e67 2062 6163 6b20 746f 2062 alling back to b 4006ef00 7569 6c74 2d69 6e20 636f 6d6d 616e 6420 uilt-in command 4006ef10 696e 7465 7270 7265 7465 722e 0a00 736c interpreter. slI don't find 0x4006eeef as a constant in the ROM, nor do I find 0x3ff9eeef, which might be an alias in the ROM1 space.