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dptOffline
Post subject:   PostPosted: 22.06.2011, 07:45



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USB to RS232 Adapters are available, they generally work, else FTDI/OTHER chips can be used.
There are PCI expansions cards too for COM ports, can be used if they can fit into the slim boxes.
So time to move on to the 'only USB' new machines.

For the Dot-Matrix printers (that many clients use), one can use the USB to parallel adapter
for old printers- fortunately new ones come (TVSE here) with USB ports.

Thanks

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DeepDayzeOffline
Post subject:   PostPosted: 22.06.2011, 14:05



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      dpt wrote:
USB to RS232 Adapters are available, they generally work, else FTDI/OTHER chips can be used.
There are PCI expansions cards too for COM ports, can be used if they can fit into the slim boxes.
So time to move on to the 'only USB' new machines.

For the Dot-Matrix printers (that many clients use), one can use the USB to parallel adapter
for old printers- fortunately new ones come (TVSE here) with USB ports.

Thanks


Yes, just check the cable or expansion card maker's site to show what printer models (with parallel connectors) are known to work with it as some may not. So if you get a USB only machine, you can still use your older peripherals with them Smile
 
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slhOffline
Post subject:   PostPosted: 22.06.2011, 19:10



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Serial USB adapters (I'm intentionally not saying RS232C) are not always a safe bet, because many serial devices uses rare serial protocols, are extremely timing sensitive (like bit-banging --> lirc_serial; which at least the USB protocol can't provide, due to IRQ-less polling principles) or abuse certain side effects usually present in classic serial ports, but not emulated well enough by USB adaptors. While in many cases a USB serial adaptor can be made working, it might take a few attempts with devices made from different adaptor chipsets to find a matching combination - however there are a few serial devices don't work reliably with any usb2serial adaptor...

This partly applies to PCI based adaptors as well, although there is a better chance to find a match (IRQ support --> better timing). However if you also need special applications under DOS/ windows, don't underestimate the problems caused by "non-standard" interface names - as most adaptors don't give you COM1/ COM2 as possible interface name, but only COM3/ COM4 - which some highly specialized proprietary applications simply don't offer; this is usually not a problem on linux.

For IEEE1284, which is mostly confined to older printers, USB adaptors or ethernet print servers can often fill the void and might even be more convenient, but for rarer IEEE1284 uses (JTag, EEPROM writers, etc.) similar issues as those raised for 'serial' may be a problem.

The lack of "real" serial/ parallel ports has been a serious problem on notebooks for quite a while already, so many newer devices already offer USB communications or at least work with common usb2serial adaptor chipsets.
 
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alexkOffline
Post subject:   PostPosted: 22.06.2011, 19:26



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I happen to use a serial device to back up information from a very old (1991?) Casio digital diary every once in a while, using Windows software under Wine in Aptosid. I wasn't even thinking that the new motherboard had no serial port. I'll probably just use an older computer to do this, maybe eventually take all the data off and move it to something a little more up to date.
 
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DeepDayzeOffline
Post subject:   PostPosted: 23.06.2011, 01:53



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      alexk wrote:
I happen to use a serial device to back up information from a very old (1991?) Casio digital diary every once in a while, using Windows software under Wine in Aptosid. I wasn't even thinking that the new motherboard had no serial port. I'll probably just use an older computer to do this, maybe eventually take all the data off and move it to something a little more up to date.


You can use a USB-to-serial cable so you can still happily sync your old Casio Smile

Have you tried finding any Linux equivalent of such software for syncing that old organizer?
 
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alexkOffline
Post subject:   PostPosted: 23.06.2011, 16:28



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      DeepDayze wrote:
You can use a USB-to-serial cable so you can still happily sync your old Casio Smile

Have you tried finding any Linux equivalent of such software for syncing that old organizer?

Yes, I could try a USB to serial adapter. I figure there are usually adapters around for legacy ports. I tried an open source linux program for backing up the digital diary and could not get it to sync and transmit data no matter what. It may depend upon the model of of diary, mine is a SF-4300B.
 
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alexkOffline
Post subject:   PostPosted: 23.06.2011, 16:56



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      dibl wrote:
Although you can find complaints about quality problems with Asus boards, I have bought 5 or 6 of them over the past three years with no issues at all. I built my current desktop system on this one:

http://usa.asus.com/Motherboards/Intel_ ... 6/P6X58DE/

It works good -- the aptosid root filesystem is on a SSD and I put a pair of WD1002FAEX drives on the Marvell 6 GiB/s controller and made a btrfs filesystem on them, and that is my data storage. i-7 950 CPU and 6GB of G.Skill ripjaws memory. Very fast.


This system sounds indeed very speedy. I have not yet tried btrfs. I will probably put my root on an SSD at some point, as it is currently on a partition of only 25-30GB. I also went with the G.Skill ripjaws memory, received but not yet tested. I have not yet received parts from Superbiiz, slower shipping than Newegg. First time ordering from Superbiiz.
 
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dptOffline
Post subject:   PostPosted: 23.06.2011, 17:55



Joined: 2010-09-11
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As per my experience, feedbacks on net and as detailed out by slh above, it is perhaps best
for me not to go for the readymade USB-only boxes to be safe, and make custom desktop with proper hardware
ports on board.
The box may not be very sleek, but work is more important. The USB to SERIAL (RS232 without suffix) will
surely have time latency and may work, and may not work and hence never used for testing purposes.

The COM3/COM4/COM5 may not a problem for me in Windows as 1) Program used for programming micro-controllers support
quite a few port numbers and 2) the VB6 programs made by me for testing or professional use check for upto COM6,
never felt the need to go for higher on laptops.

Thanks slh, there is no end to what we can learn. There never will be.

EDIT: And Thanks to everyone here too.

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alexkOffline
Post subject:   PostPosted: 03.09.2011, 19:01



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Update on this build: I had to get the initial Intel DZ68DB motherboard RMA'd as it had a couple of issues including losing all sound after a few days (extensively tested to rule out non-motherboard issues). The new board is working well. My only real criticism beyond getting a faulty motherboard is that the latest BIOS is slow to start up on a soft reboot, a known issue. This motherboard also didn't very much like the original 1600 MHz G.Skill RAM that I put in it but is fine with Ripjaws X series 1333 MHz RAM that I replaced it with. I also had an unrelated issue with a new power supply which was the same with both motherboards, but fortunately I had a good spare power supply.

The Intel graphics are working well with recent kernels, even with some 3D gaming, though I seem to get some small display artifacts with Speed Dreams. Video conversion is very fast in HandBrake, 5 minutes to transcribe a full-length DVD to Ipod format.

Upon boot up, I was getting mtrr errors of this sort:
      Code:
mtrr: type mismatch for e0000000,10000000 old:write-back new:write-combining
[drm]MTR allocation failed. Graphics performance may suffer.

Adding "enable_mtrr_cleanup" to the linux command line in /etc/default/grub made the error messages disappear and performance seems to be good.
 
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alexkOffline
Post subject:   PostPosted: 03.09.2011, 20:42



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This is the first destkop among mainly three I've used with Linux on which suspend mode works well. My previous Epox motherboard would wake once from suspend mode, then you'd have to restart the network connection, but it would never wake if suspended more than once.
 
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BarlafussOffline
Post subject:   PostPosted: 04.09.2011, 08:04



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thanks alexk to share Your experience with the new system.
I'm also on going to change my (very) old desktop, so I'm collecting any post can help/support me in the choice .
Barlafuss
 
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alexkOffline
Post subject:   PostPosted: 04.09.2011, 10:35



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This system is running well now, except for the occasional graphics issue probably related to the Intel drivers, for example this one and this one. I also had a worse issue where X was crashing back to a login prompt when running at least some OpenGL screensavers in random mode. I worked around that by turning off OpenGL screensavers. The Intel drivers seem to be improving as I've seen clear progress with kernel upgrades, currently running 3.0-1.slh.6-aptosid-amd64, not yet tried anything more recent.

A note on reseating heatsinks: upon receiving the replacement Intel motherboard, I at first reseated the Intel heatsink using the original thermal compound that came with it, still applied, since I had only used the CPU for a week. I got pretty good temperatures doing this, but decided to try reseating again with some 5-year old Arctic Silver 5 compound, following the instructions carefully. This gave me temperatures that seemed quite a lot worse, even after a fair amount of break-in and taking into account ambient temperatures. In the end, after trying that method a couple of times, I reseated once more using these Antec instructions, still using the Arctic Silver 5 with the stock Intel heatsink and the result has been quite a bit better temperatures.
 
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