EA Base Board & MBED : I/O Problems

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EA Base Board & MBED : I/O Problems

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by caprock on Tue Mar 30 15:31:10 MST 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.
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by brucesegal on Wed Mar 31 12:07:40 MST 2010
I understand.

I can say that the baseboard RGB leds are connected as documented in the manual and schematic.
A program that toggles bits PIO1-2, PIO1-9, and PIO1-10 will toggle the various leds.

I may borrow an mbed from a friend and see whats up.
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by caprock on Wed Mar 31 11:00:46 MST 2010
Thanks.

No doubt that the EA code works but I may have a defective unit, either mbed or base. This is the reason for the post. Seems that my hardware is behaving differently from others.

That is the only explanation that I can come up with why can't clear all 7-segments, and why when I write to each segment in bit order the results do not match. Simple test 7-segment: spi.write(0xbf) - bit 6 on my board this is the Decimal point but all docs say that the Decimal point is spi.write(0xdf) - bit 5.

I cannot understand the descrepancy but since I only have one base board  and one mbed I must reach out to others to confirm one way or another.

In the meantime I have ordered an additional Base board and the LCPXpresso LCP1343 - perhaps this will help.
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by brucesegal on Wed Mar 31 10:42:23 MST 2010
The demo software supplied by EA works with the baseboard and the lpc1114 or lpc1343 (i've tried both) correctly. At least the 7 segment display counts  and the RGB works.

I haven't looked closely at the code to see if the schematic differs from the code yet. Something else on the list of things to do.

I did write some test code to work with the RGB leds. I will try to find it and post it.
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