The 1000-traces-puzzle


_wb_

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What is the difference between a host port and a console port? How do you use a console port? Can you connect it to some other computer and somehow get a Pyra tty? (if so, what would be the command to "telnet" into the Pyra like that?)
 

hns

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What is the difference between a host port and a console port? How do you use a console port? Can you connect it to some other computer and somehow get a Pyra tty? (if so, what would be the command to "telnet" into the Pyra like that?)
The console port provides an FT232 USB to serial converter connected to /dev/ttyO2 of the Linux running on the Pyra. This allows to watch boot messages from MLO, U-Boot and the Kernel. So the external device must be an USB host and this port is just an USB slave. But you might need some FTDI driver to access the FT232 as a serial port (/dev/tty$something) on your host.To "telnet" into the Pyra you just have to answer the login: and passwd: prompts presented by getty.

The reason to choose this solution is that we wanted to have a separate charger input (to allow the USB3 port to be switched to host mode). Therefore we already had a need for a standard socket (micro-USB).This allows to connect the Pyra to some off-the-shelf charger or notebook.

Adding the FT232 chip and connecting it to the UART port of the OMAP was quite obvious to do. Basically it replaces an external RS232 converter for the expansion port of the OpenPandora.
 

_wb_

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What is the difference between a host port and a console port? How do you use a console port? Can you connect it to some other computer and somehow get a Pyra tty? (if so, what would be the command to "telnet" into the Pyra like that?)
The console port provides an FT232 USB to serial converter connected to /dev/ttyO2 of the Linux running on the Pyra. This allows to watch boot messages from MLO, U-Boot and the Kernel. So the external device must be an USB host and this port is just an USB slave. But you might need some FTDI driver to access the FT232 as a serial port (/dev/tty$something) on your host.
To "telnet" into the Pyra you just have to answer the login: and passwd: prompts presented by getty.


The reason to choose this solution is that we wanted to have a separate charger input (to allow the USB3 port to be switched to host mode). Therefore we already had a need for a standard socket (micro-USB).This allows to connect the Pyra to some off-the-shelf charger or notebook.


Adding the FT232 chip and connecting it to the UART port of the OMAP was quite obvious to do. Basically it replaces an external RS232 converter for the expansion port of the OpenPandora.
Thanks for the details. Does this mean that this charging/debug µUSB port is not a USB port from the OMAP5 point of view, but connected to its "Multichannel Buffered Serial Port" (http://www.ti.com/product/omap5432) ?

What kind of transfer rate could theoretically be achieved through this port?

Also, a completely unrelated question: what is the current status regarding software support for the 2D graphics core, Vivante GC320?
 

Grench

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Pyra base unit plus the eSATA adapter plus something like one of these:

http://www.amazon.com/Port-Multiplier-SATA-hardware-controller/dp/B004JPHAF0/

http://www.amazon.com/multiplier-hardware-RAID0-CLONE-Controller/dp/B004JPUZWU/

http://www.amazon.com/Oodelay-eSATA-Port-Multiplier-Controller/dp/B00PZ7347E/

If I understand it right, those can be ganged too. I.e. if you got 6 of them you could have 25 SATA devices connected to a single eSATA port on a Pyra. You could even have them all running in a multi-tier RAID 5. Would you call that RAID 55? RAID 5+5? Raid 5^5? Or just plain silly?

Add in an external case and PSU for the drives. Maybe a multi-drive hot swap SATA cage or two...

At that point you can have a pretty nifty NAS running a full Debian install.

The hypothetical 'could' and the 'should' may be two different things though.
 You can chain all sorts of things together, but in the end, it will still be no more than 300MB/s going into the OMAP5.

If the RAID is just for reliability, that doesn't matter, but if it's mostly for performance, then it does not really help much.
Array speed isn't really the bottleneck on a NAS box though. RAID5 is essentially for data protection so that the array can survive single drive failures.

In this scenario the Pyra NAS throughput capability limit is actually the networking. That either happens through a USB 2 or USB 3 dongle or WiFi. Either of those are going to max out far, far less than the 300 MB/s that the single port SATA array. Even if the SATA array topped out at 100 MB/s it would still be faster than the network connection.

The fastest commercial NAS boxes on the market have very fancy network connections in them capable of maxing out the gigabit wired port. Even under ideal conditions with a fancy router/switch or direct connection to clients they top out between 70 and 80 MB/s.

Although the Pyra as NAS scenario might be entertaining to build as a hobby project, the end result is likely to be more expensive than simply building a home server with one or two old AMD 2419ee CPUs, an old hot swap SATA/SAS server case, a hardware SATA RAID controller and a few 2TB or so drives.

Just because it can be done - doesn't mean that it should be done. Cool concept though.
 

_wb_

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Pyra base unit plus the eSATA adapter plus something like one of these:

http://www.amazon.com/Port-Multiplier-SATA-hardware-controller/dp/B004JPHAF0/

http://www.amazon.com/multiplier-hardware-RAID0-CLONE-Controller/dp/B004JPUZWU/

http://www.amazon.com/Oodelay-eSATA-Port-Multiplier-Controller/dp/B00PZ7347E/


If I understand it right, those can be ganged too. I.e. if you got 6 of them you could have 25 SATA devices connected to a single eSATA port on a Pyra. You could even have them all running in a multi-tier RAID 5. Would you call that RAID 55? RAID 5+5? Raid 5^5? Or just plain silly?


Add in an external case and PSU for the drives. Maybe a multi-drive hot swap SATA cage or two...


At that point you can have a pretty nifty NAS running a full Debian install.


The hypothetical 'could' and the 'should' may be two different things though.
 
You can chain all sorts of things together, but in the end, it will still be no more than 300MB/s going into the OMAP5.


If the RAID is just for reliability, that doesn't matter, but if it's mostly for performance, then it does not really help much.
Array speed isn't really the bottleneck on a NAS box though. RAID5 is essentially for data protection so that the array can survive single drive failures.


In this scenario the Pyra NAS throughput capability limit is actually the networking. That either happens through a USB 2 or USB 3 dongle or WiFi. Either of those are going to max out far, far less than the 300 MB/s that the single port SATA array. Even if the SATA array topped out at 100 MB/s it would still be faster than the network connection.


The fastest commercial NAS boxes on the market have very fancy network connections in them capable of maxing out the gigabit wired port. Even under ideal conditions with a fancy router/switch or direct connection to clients they top out between 70 and 80 MB/s.


Although the Pyra as NAS scenario might be entertaining to build as a hobby project, the end result is likely to be more expensive than simply building a home server with one or two old AMD 2419ee CPUs, an old hot swap SATA/SAS server case, a hardware SATA RAID controller and a few 2TB or so drives.


Just because it can be done - doesn't mean that it should be done. Cool concept though.
I'm not talking about using a Pyra as a NAS, that would be quite expensive indeed. I'm talking about a Pyra-CPU-board based NAS.

OMAP5 could do Ethernet via USB. Since USB 3.0 can do 5Gbit/s (625MB/s), it should easily be able to max out Gigabit Ethernet, and theoretically I guess it could be connected to 10 Gigabit Ethernet.

So the 300MB/s SATA connection could still be the bottleneck if everything else is sufficiently fast.

Anyway, sure, you can get a cheap home server based on any desktop PC. But I'm interested in something low-power (after all it's going to be running 24/7), without any moving parts that produce noise. Desktop PCs tend to be relatively power-hungry, with CPU fans and spinning disks that produce noise.

How much would a Pyra without screen, without keyboard etc cost? If ED could sell a full Pyra for, say, 600 EUR, then I would estimate that he could sell a significantly simplified Pyra-like home server for less than half of that price. Perhaps the simplification could even be done by taking the Pyra main PCB and not populating the non-used parts (wifi/3G/rumble/battery gauge chip/backlight leds/whatever), adding a small extra PCB for Ethernet and SATA, and designing a case around it (it does not have to be as tight and strong as the Pyra, so designing such a case should be easier).
 

hns

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What is the difference between a host port and a console port? How do you use a console port? Can you connect it to some other computer and somehow get a Pyra tty? (if so, what would be the command to "telnet" into the Pyra like that?)
The console port provides an FT232 USB to serial converter connected to /dev/ttyO2 of the Linux running on the Pyra. This allows to watch boot messages from MLO, U-Boot and the Kernel. So the external device must be an USB host and this port is just an USB slave. But you might need some FTDI driver to access the FT232 as a serial port (/dev/tty$something) on your host.To "telnet" into the Pyra you just have to answer the login: and passwd: prompts presented by getty.

The reason to choose this solution is that we wanted to have a separate charger input (to allow the USB3 port to be switched to host mode). Therefore we already had a need for a standard socket (micro-USB).This allows to connect the Pyra to some off-the-shelf charger or notebook.

Adding the FT232 chip and connecting it to the UART port of the OMAP was quite obvious to do. Basically it replaces an external RS232 converter for the expansion port of the OpenPandora.
 Thanks for the details. Does this mean that this charging/debug µUSB port is not a USB port from the OMAP5 point of view, but connected to its "Multichannel Buffered Serial Port" (http://www.ti.com/product/omap5432) ?

What kind of transfer rate could theoretically be achieved through this port?
It is connected to an UART port of the OMAP5. That one can up to 3 MBit/s but one has to check the speed options of the FT232. During boot, it runs at 115200 bit/s.
 

Grench

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What is the difference between a host port and a console port? How do you use a console port? Can you connect it to some other computer and somehow get a Pyra tty? (if so, what would be the command to "telnet" into the Pyra like that?)
The console port provides an FT232 USB to serial converter connected to /dev/ttyO2 of the Linux running on the Pyra. This allows to watch boot messages from MLO, U-Boot and the Kernel. So the external device must be an USB host and this port is just an USB slave. But you might need some FTDI driver to access the FT232 as a serial port (/dev/tty$something) on your host.To "telnet" into the Pyra you just have to answer the login: and passwd: prompts presented by getty.

The reason to choose this solution is that we wanted to have a separate charger input (to allow the USB3 port to be switched to host mode). Therefore we already had a need for a standard socket (micro-USB).This allows to connect the Pyra to some off-the-shelf charger or notebook.

Adding the FT232 chip and connecting it to the UART port of the OMAP was quite obvious to do. Basically it replaces an external RS232 converter for the expansion port of the OpenPandora.
 Thanks for the details. Does this mean that this charging/debug µUSB port is not a USB port from the OMAP5 point of view, but connected to its "Multichannel Buffered Serial Port" (http://www.ti.com/product/omap5432) ?

What kind of transfer rate could theoretically be achieved through this port?
It is connected to an UART port of the OMAP5. That one can up to 3 MBit/s but one has to check the speed options of the FT232. During boot, it runs at 115200 bit/s.
Must... refrain... from building microUSB to RS232 adapter to run old school modem that is physically larger than the Pyra ON a Pyra...

Seriously - that serial port could be very handy if someone wanted to run laboratory automation equipment or holiday light shows off of the Pyra. Having it shaped like a microUSB simply makes it compact enough to exist - which is good.
 

Binky

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How symetric is the connection logically?

Presumably the pyra thinks its on the slave end of the serial (as well as of the USB) conection, if there is one.

Anyway, why aren't your christmas lights Cloud Enabled? :p
 

rygD

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What is the difference between a host port and a console port? How do you use a console port? Can you connect it to some other computer and somehow get a Pyra tty? (if so, what would be the command to "telnet" into the Pyra like that?)
The console port provides an FT232 USB to serial converter connected to /dev/ttyO2 of the Linux running on the Pyra. This allows to watch boot messages from MLO, U-Boot and the Kernel. So the external device must be an USB host and this port is just an USB slave. But you might need some FTDI driver to access the FT232 as a serial port (/dev/tty$something) on your host.
To "telnet" into the Pyra you just have to answer the login: and passwd: prompts presented by getty.


The reason to choose this solution is that we wanted to have a separate charger input (to allow the USB3 port to be switched to host mode). Therefore we already had a need for a standard socket (micro-USB).This allows to connect the Pyra to some off-the-shelf charger or notebook.


Adding the FT232 chip and connecting it to the UART port of the OMAP was quite obvious to do. Basically it replaces an external RS232 converter for the expansion port of the OpenPandora.
 
Thanks for the details. Does this mean that this charging/debug µUSB port is not a USB port from the OMAP5 point of view, but connected to its "Multichannel Buffered Serial Port" (http://www.ti.com/product/omap5432) ?


What kind of transfer rate could theoretically be achieved through this port?
It is connected to an UART port of the OMAP5. That one can up to 3 MBit/s but one has to check the speed options of the FT232. During boot, it runs at 115200 bit/s.
Must... refrain... from building microUSB to RS232 adapter to run old school modem that is physically larger than the Pyra ON a Pyra...


Seriously - that serial port could be very handy if someone wanted to run laboratory automation equipment or holiday light shows off of the Pyra. Having it shaped like a microUSB simply makes it compact enough to exist - which is good.
You are not alone.
 

rygD

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Btw are any concept pictures of the caps available?
I wasn't very pleased to hear the key had thick transparent edges around the black paint. I hope this is no longer the case.
 
No, that's the reason we're now using plastic caps.
I can make pictures once the design has been changed, which is in about 1,5 weeks (the designer is currently on holidays for this week).
If it isn't too much trouble, can we get those pictures while we wait for the poll to finish up?
 

levi

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Hm, we checked with various big ones. According to them, it's not physically possible.
If you know one, let me know and I'll contact them. Depending on the price, we would make use of them.
http://www.eurocircuits.com/can make 10-layer within 3 days, or so they say in their price calculator.
ED's already found a supplier who can make 10 layer boards with a rapid turnaround, which is why he's hopefully able to demo something at the next expo in August.
 

Zink

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ED's already found a supplier who can make 10 layer boards with a rapid turnaround, which is why he's hopefully able to demo something at the next expo in August.
Yes, I saw the other topic only after posting that :) .
 

EvilDragon

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Hm, we checked with various big ones. According to them, it's not physically possible.


If you know one, let me know and I'll contact them. Depending on the price, we would make use of them.
http://www.eurocircuits.com/can make 10-layer within 3 days, or so they say in their price calculator.
ED's already found a supplier who can make 10 layer boards with a rapid turnaround, which is why he's hopefully able to demo something at the next expo in August.
And 10 layer is not 10 layer.


The company we use doubled the production time and even had to send it outwards, because the PCB was too complex for them (MicroVias, etc.)


My guess is that they can produce simple 10 layer boards within the 3 days and use it just for advertising :)
 

fusion_power

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And 10 layer is not 10 layer.

The company we use doubled the production time and even had to send it outwards, because the PCB was too complex for them (MicroVias, etc.)

My guess is that they can produce simple 10 layer boards within the 3 days and use it just for advertising :)
Sounds indeed more like markeing brabble then, right? :D Well why are actualy so many traces onto this little board? Is it normal to connect an OMAP5 soc to the environment or do other parts need so many wires on the CPU board?
 

TrashyMG

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Sounds indeed more like markeing brabble then, right? Well why are actualy so many traces onto this little board? Is it normal to connect an OMAP5 soc to the environment or do other parts need so many wires on the CPU board?

The CPU module is essentially a complete computing device everything except peripherals like the keyboard, audio amplifier and such... So the SoC itself, eMMC memory, 4 SDRAM modules, supporting circuitry the two connectors that interfaces the large main board with what appears to be 80+ connectors each... so yeah a lot of traces. 
 
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Natsu

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I'm liking the look of the (back side of) case. Lol
 
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