[Arm-netbook] 75USD A10 android USB key

Mon May 28 20:59:49 BST 2012

Thanks, Tom, hope to see similar product soon.

About HDMI - it is somehow controversal - having full size male HDMI on the
stick will bring the size up. Having small miniHDMI (like tablets), or even
microHDMI (like smartphones) will reduce the size. But than you need a
cable.
In some cases plugging such big dongle (with full size connector) is simply
bad because it might not fit given TVs (depending on the angle of the
connector and placement behind the TV). And again you need additional cable
for power supply. Many (if not all) modern TVs export USB connector where
you can take the power supply directly from the TV. Some limit USB to
service use only, some give full media player features and even USB-2-LAN
support. But having available power without additional adapter and so on is
an extra. Sure you cannot rely only on this, because this power goes away
when TV is off, but it is a feature you don't want to leave out. Probably
microUSB is fine for power supply, and maybe for USB client (device) mode
(for ADB or ADK or LiveSuit). There are a lot of low end devices (like
TP-LINK "3G" routers) that use micro USB type of power adapter. A lot of
mobile phones already employ microUSB for charging. And microUSB OTG is
really tiny form factor for dual-role USB connection.
I hope extension connections could be made without affecting the bill of
materials - I have seen a lot of CPU modules for tablets (with InfoTMIC
SoC, and with Telechips, and some Samsung ones). They use no connectors but
simply plated vias on the edge of the pcb like extension header (similar to
common bluetooth modules with CSR seen on ebay). I think this is really
cheap to manufacture. Another way is to make one of the sides of the PCB
like SODIMM module. So the baseboard will have SODIMM connector (slot) to
host the module.
Freescale are using PCI express form factor - their tower system (and
KwikStick module) have plated contacts with footprint of a dummy PCI-E x16
card. This plugs in PCI-E x16 slot ( I use desoldered one from defective PC
mainboard). Probably x16 is not needed but having 20 pins is a good start.
Having 40+ pins might even route out the LCD interface and this opens the
module for various applications.

My point is that trying to make the smallest possible android TV dongle is
a bad direction - with all my respect to the people in Allwinner, you
cannot compete with TI or Samsung and their Package-on-package solution. We
all have seen pandaboard and Omap4 with 1GByte of RAM in package that is
probably half the area of the A10 chip. So the title for "world tiniest
stick" will go to the company that makes stick with TI or Samsung.
There is already one stick with A10, this MK802, probably soon will come
others, with A10 or different chips. If somebody wants to make something
new, that targets other audience, that it has to provide different
features. My proposal is to focus on this audience that is reading this
list, and probably think on how to make it friendly for others, like
Arduino lovers. In this area you don't want to squeze out each square mm of
the board.
Olimex will make something with A13 - this is nice, and covers some
applications. In parallel, somebody might want to do the A10 type, but
opening it for bigger customization. If Olimex make a A10 variant, they
will try to fit all possible interfaces to one "PCBA". This is already seen
with Mele or soon-to-come next PCBAs for STB with A10. There is nothing
wrong with Olimex style, but I don't want to pay the premium of several
non-needed connectors and chips that I would not use (and another premium
that the product is made in limited quanities because it can never fit the
BOM of serial production). They will have to put RS232 on board, but what
if I need TTL level UART? Should I desolder MAX and remove the connector?
Some of us prefer to have TTL level, and to add level shifter externally,
only if needed. Some of us don't want to invest in developing 6-layer board
when it will be simply a copy of reference design. I want to make simple
breadboard, than 2 or 4-layer custom board that will host only some sensors
or microcontroller that will do "my special things". Knowing the high speed
differential signaling is out of my way, and somebody has soldered the BGAs
for extra $20. I can live with this +$20 until my production is below,
let's say, 1000 pieces. Than I can think of custom PCB. But 20 developers
like me, with 1000 modules, will bring the price of the module down to the
real BOM. Something that can never happen if the board is more like
development board than System-on-module. (or, make it 200 developers X 100
pieces, or 2000 developers X 10 pieces, or, at the end, 20000 Arduino users
X 1?).
You know that some arduino shields with ethernet or wi-fi are selling for
40USD and above - without the actual Arduino for 20-30 more? What is the
reason behing this - I think that as long as the product is easy to work
with, they would not mind buying complete system for $50?
If Hyston PCBA is selling for $30, I think that $50 for a board with
extension lines should be possible? If Allwinner (or Wits) have reference
design for similar product, how much work would it be to add lines to the
extension, and route them?

In general, USB HOST is nice alternative too - I can take $2 PIC with USB,
or FTDI and do my things, and this is my choice up to now. But when I need
3G networking, that I need 2 USB host ports (or a hub). But this does not
mean that I want 7-port hub intergrated into the stick, nether 24V I/O with
galvanic isolation ...

2012/5/28 cnxsoft <cnxsoft at cnx-software.com>

>  On 28/05/2012 20:14, Tom Cubie wrote:
>
>
>
> On Mon, May 28, 2012 at 1:48 PM, krasi gichev <krasimirr at gmail.com> wrote:
>
>> It is already available here for $73:
>>
>> http://www.merimobiles.com/MK802_Allwinner_A10_Android_4_0_TV_Box_2160P_HDMI_p/meri4833.htm
>>
>>
> my friends is going to build such a product(without the case), A10, HDMI,
> small size,
> target at $49, will it be popular?
>
>>
>>    This type of board could be popular, especially once you get Linux
> distributions and XBMC working. If the product is popular, custom cases
> will appear like it's done for the Raspberry Pi.
> To save cost he might consider scrapping the NAND flash and let people use
> a microSD card to boot the system. The main drawback with this is possible
> performance degradation with SD, but I have not seen benchmarks about this.
> If your friend can make a case that can be plugged directly into the TV
> (HDMI) without cable and powered by USB (small USB cable to the TV USB
> port) it will be even more successful.
>
>
>
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