December 9, 2016
Orange Pi PC 2
I bought one of these in November of 2016, it is very much like the Orange Pi PC,
but with the Allwinner H5 chip instead of the H3 chip.
As of August, 2020 these seem to be no longer available.
I like this board a lot, but I can see why people get confused by it.
There is no power LED, in fact no sign of life until you plug in an SD card
with a valid boot setup. I am sure many people think their boards are dead.
The Orange Pi designers should fix this. There ought to be a real power LED along
with an honest to goodness hardware reset button.
The H5 is more or less identical to the A64, but with a fancier graphics section and no PMIC (power management IC).
These are all essentially the same peripherals around different cores.
When you jump from the H3 to the A64, you get the armv8 A53 core instead of the armv7 A7 core.
When you jump from the A64 to the H5 you get a Mali 450 GPU instead of a Mali 400.
I never use the GPU, so either an A64 or H5 is fine by me,
There are other fussy differences, in particular the pinmux setup is different.
The board has onboard flash in a MXIC 25L1606E chip. This is 2 megabytes as 16M x 1 bit.
I am not sure what it is good for.
Cortex-A53 versus Cortex-A7
The A53 is a 64 bit chip, but I can't see how that matters with only 1G of RAM.
However, the A53 performs somewhat better at the same clock rate than the A7.
The claim is as much as 40-50 percent faster on integer code,
although when I run the Dhrystone benchmark I see only about a 20 percent improvement.
Power and such
It receives power via a small diameter (4 x 1.7 mm) barrel connector.
This is just like the "Orange Pi PC". I am using a 5V 2A supply made by
Toshiba with complete success. I'll bet people have trouble with cheap
supplies that barely meet the 2A specification.
Some folks say the H5 chip can run hot. And a viable strategy to avoid this is to
downclock the chip! Why not? True of the H3 chip as well.
In fact, I have yet to find a specification for the PC 2 clock speed.
Serial Console
I use a CP2102 USB to serial gadget to connect to the 3 pin serial console.
It works great.
First experiences
My unit simply acts dead. With the power supply connected there are no lights at all,
not even on the ethernet jack. I checked voltage at the barrel connector and see 5.09 volts.
I also check on the LM1117 chip on the back of the board and see 3.3 volts coming from it.
However, I have not yet plugged in an SD card. I had hopes that there would be something
in the 8M of NOR flash onboard that might run. Not so, everything is fine as it turns
out, it just needs a valid boot setup on an SD card.
Have any comments? Questions?
Drop me a line!
Tom's electronics pages / tom@mmto.org