If I understand the manual, each leg in each of the 7 segment displays is labeled with a letter A-G. These letters then map to specific bits in a byte - 1 byte for each of the 4 displays. Setting a bit turns on the corresponding leg while not setting it leaves it off.
With this understanding, I tried to turn on all the A segments by sending
[163][1][1][1][1]
Instead of the A segment in each display turning on, the displays all showed a 1. Further testing shows that if I send the numbers 1-9 for any of the displays, they will display the number sent. Sending the number 10 or greater turns on various combinations of the segments.
I was able to activate individual segments with the following numbers:
63 G
64 A
65 B
66 C
67 D
68 E
69 F
However, I haven't been able to determine how the bytes sent affect the individual segments. Either I don't understand the manual or Digit LEDs Raw does not work as the manual specifies.
UPDATE 03JUNE2016
I have confirmed this behavior exists in the following firmware versions:
- r3-robot/tags/release-3.4.1:5858 CLEAN
- r3_robot/tags/release-3.2.6:4975 CLEAN