EA Base Board & MBED : I/O problems

30 Mar 2010

I have the Embedded Artists Base Board (EA-XPR-021) with the MBED installed and am having some difficulty getting certain interfaces to work. Chances are that I have mis-understood a pinout, but somethings just look questionable. And to top it off, support at Embedded Artists cannot seem to concur. Perhaps one of these two boards are responsible.

I have published my simple tests at: http://mbed.org/users/caprock/programs/EA_SegIoTest/602vg/ The test starts with the "Group Segments & RGB Led". Depress the Joystick to advance to "March Bits b0 => b7". Depress the Joystick to advance to "March Segments SA => SG, DP". (note: The EA board options are as set at the factory)

At the moment I see three problems:

1) The 7-segment display always has the lower right segment On.

2) This 7-segment pinout and segent order does not seem to match the schematic. The schematic shows the display with a 180 degree rotation, placing the decimal point at the upper left. The published Rev A has b7 <- b0 as:  FC.BAGED (correct rotation) but the actual segment order seems to be:  b7 <- b0 as:  F.EDGBAC (the period . is the Decimal Point). Another observation: the SPI/OLED interface is Ok.

3) The RGB interface does not seem to work. (not reported yet) With the "Group Segments & RGB Led" test, I am writing 1: RGB_RED (0x01), 2: RGB_GREEN (0x04), 3: RGB_BLUE (0x02), 4: All (0x07). What I seem to get is: 1: Red, 2: none, 3: none, 4: Red + Blue

At the moment I am totally confused and would really appreciate someone with theses boards running the test program and reply with the results.