Well, something went really wrong here. Obviously it's supposed to keep blinking, not just stop.
The numbers 16C0 and 0483 are correct for Teensy when running your program, so at least that's a good sign.
The first step from here is to open the Help > Verbose Info window from Teensy Loader. Then press the white pushbutton on your Teensy. What text appears in the Verbose Info window?
Thanks Paul, here are last few lines of verbose info:
(much more above this...If you need more, I can send the whole thing)
10:11:44: flash, block=4, bs=1024, auto=1
10:11:44: flash, block=5, bs=1024, auto=1
10:11:44: flash, block=6, bs=1024, auto=1
10:11:44: HID/win32: waiting for device
10:11:44: flash, block=7, bs=1024, auto=1
10:11:44: flash, block=8, bs=1024, auto=1
10:11:44: flash, block=9, bs=1024, auto=1
10:11:44: flash, block=10, bs=1024, auto=1
10:11:44: HID/win32: waiting for device
10:11:44: flash, block=11, bs=1024, auto=1
10:11:44: flash, block=12, bs=1024, auto=1
10:11:44: flash, block=13, bs=1024, auto=1
10:11:44: HID/win32: waiting for device
10:11:44: flash, block=14, bs=1024, auto=1
10:11:44: flash, block=15, bs=1024, auto=1
10:11:44: flash, block=16, bs=1024, auto=1
10:11:44: HID/win32: waiting for device
10:11:44: flash, block=17, bs=1024, auto=1
10:11:44: flash, block=18, bs=1024, auto=1
10:11:44: flash, block=19, bs=1024, auto=1
10:11:44: sending reboot
10:11:44: begin wait_until_offline
10:11:44: offline, waited 4
10:11:44: end operation
10:11:44: set background IMG_REBOOT_OK
10:11:44: redraw timer set, image 14 to show for 1200 ms
10:11:44: HID/win32: vid:05AC pid:0245 ver:0108
10:11:44: HID/win32: vid:05AC pid:0245 ver:0108
10:11:44: HID/win32: vid:05AC pid:8242 ver:0016
10:11:46: redraw, image 9
Here is what happened today:
Cold boot into bootcamp, Win 7HP on a Mac, plugged in Teensy 3.5, no IDE or Teensy loader yet, LED on board blinks on for one sec, off for one sec.
Next I opened Arduino IDE 1.6.12. Tried to upload a modified, faster blink sketch, got Teensy loader, did verbose info, got same red error msg:
Teensy did not respond to a USB-based request to automatically reboot. Please press the PROGRAM MODE BUTTON on your Teensy to upload your sketch. LED still bllinking one sec on, one sec off.
Next tried pressing (not holding) reset button, then upload new sketch, Teensy loader said "boot OK", got same error msg. as above, still blinking one sec. on, one sec. off.
Bottom line: cannot load a new sketch. Hardware seems healthy.
N.B. I have used Arduino IDE for four years on this machine with no operator induced problems, but I have had some weirdness running some ham radio programs. I will try all of the above on a fresh install on a "pure" win 7 machine and see what happens.
Thanks again and hope you can help solve this.
P.S. I looked for the Teensy loader verbose log file, which I suspect is purposely well hidden.
Is there a way to erase or archive it and start a new log so that I log only the current session?