The messages to which I referred were sent from the diagnostic program pre-loaded on board as I received it. I since have made several puzzling observations to report:
(1) I think it is safe to conclude the USB programmer board I received is defective and needs to be replaced.
(2) I attempted to upload the Blink program using the Adafruit cable with only the Ground, VCC, RX, and TX leads connected. The upload failed.
(3) I connected the Adifruit RTS lead to the AmbaSat's DTR lead and attempted the upload.
(4) The upload failed, but much to my surprise, the output of the IDE serial monitor changed. It reported "Checking I2C device..." for the first time and then reported values that change as expected as I covered/uncovered the sensor. See below.
14:20:19.591 -> RAW:0
14:20:19.638 -> UV_INDEX:0
14:20:19.638 -> IR:-5246 lux
14:20:19.638 -> Visible:14259 lux
*** AFTER ATTEMPTING UPLOAD ***
14:20:21.367 -> Checking I2C device...
14:20:21.929 -> Found Si1132
14:20:21.976 -> RAW:0
14:20:22.023 -> UV_INDEX:0
14:20:22.023 -> IR:392 lux
14:20:22.023 -> Visible:565 lux
(5) Thus I'm assuming the sensor and AmbaSat are functional, and problem exists with the programmer. I will request a replacement from Jackie.
Question: Do you have any suggestions has to how I might use the Adafruit cable with the AmbaSat? They are both USB to TTL serial interfaces, but the RTS/CTS and DTR/SS interfaces and (drivers perhaps) are different.
Thanks for your help.