# USB video/ATSC/NTSC-in for DirecTivos?



## rlw (Mar 1, 2007)

From scanning these forums, it looks like the Samsung SIR S4040R has a USB port. Would it be possible to install a different Linux (MythTV, etc.), the appropriate drivers, and a USB-based NTSC/ATSC receiver or USB-based video-in device to make the DirecTivos record off-air or video-in?

Has anyone tried this?

Thanks,

RLW


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## Finnstang (Sep 11, 2003)

Not really. Search and you can find threads for others who have asked the same or similar questions and you will be able to read the why.


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## rlw (Mar 1, 2007)

Finnstang,

Thanks for taking the time to reply.

I searched the forums, and found lots of replies that say it can't be done, but nobody seems to mention *why* it can't be done.

Here's what *I think* I know about the Series 2 DirecTivos (specifically, the Samsung SIR S4040R):

It has a 40 GB hard drive.
It has a master/slave IDE controller (that's how you add a "Drive B" to it).
It runs some kind of Linux.
It has an infrared sensor, and probably runs LIRC or a variant that responds to an infrared remote control.
It has a USB port (I think, since you can buy a network interface for it, and the DVRupgrade website mentions being able to add a USB network adapter to it).
It has two DirecTV satellite tuners built in, and it doesn't do any kind of video processing on the input side. It just "records" the raw, compressed, encrypted DirecTV feed from the tuner(s).
It *does not *have any facility for video-in, nor does it have an ATSC or NTSC tuner.
It has a modem -- that's how it "calls home"
If you want to add a "Drive B", it has to be "blessed" (I assume that means it has to have a particular format and partition-type, and some sort of cookie that tells the Tivo it's OK to use this drive).
Some of the upgrades install scripts and software on the hard drive to handle remote web access, networking, modified user interfaces, etc.
Here's a short list of the zillions of things I *don't* know about it:

Processor
Processor speed
Memory, memory type, size, are there any memory expansion slots?
USB bus type (USB1.1/USB2.0?)
Additional I/O (serial/modem type/etc.)
Does the Linux boot from/run in EEPROM, or does it boot off the hard drive?
So, what we have here is a Linux box, with NTSC video out, a USB port, and an app running under Linux that does the "Tivo" part.

If the OS resides on and boots from the hard drive, it seems to me that one could install another version of Linux on a hard drive and install that in the DirecTivo.

If it boots and runs from EEPROM, that presents a stickier problem. It still seems that there is an /etc/rc.d (or equivalent startup mechanism) that could contain a script that would boot a different kernel off the hard drive. I noticed on some of the upgrade websites that the "upgrade" installed scripts in the startup area.

With the correct driver(s), you could get a wireless USB adapter working (I have a handful of PRISM-based 80211b adapters). With a 4 port hub, you could add a keyboard, mouse, and a USB-based video input adapter or TV tuner (NTSC/ATSC) if drivers are available for Linux. A DVD burner could be added to the slave connector on the IDE controller.

Taking a look at the MythTV website, Hauppauge makes a capture device called a WinTV-PVR-USB2 that has a Linux driver available. The only problem is that the somewhat easier KnoppMyth distro doesn't support it, although the wiki says that a driver is available (my guess is that KnoppMyth doesn't support it "out of the box")

Anyway, I still can't see why it's "impossible" to hack a DirecTivo into a more generic MythTV box, probably upgradeable at some point to handle ATSC/HD (if the processor can handle the load).

The one I found for $30 might be fun just to play with -- what the heck? The 40GB drive is almost worth that...

I'd be curious to know if anyone else shares my view, or can explain why it would be impossible to do. A link to a particular thread that explains it would be useful, too...

Thanks,

RLW


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## JWThiers (Apr 13, 2005)

While a tivo (and by extension a direcTv Tivo) are basically computers running a very customized linux, I believe all of the hardware is custom. The hardware by computer standards is VERY underpowered, that is the main reason. It might not be impossible, just not worth the effort when you can get a cheap used PC and do what you want and spend little or nothing and not have to hack not only the linux OS, but probably also whatever other software you want to use and then probably still not work right.


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## Joe Smith (Aug 1, 2003)

rwl said:


> things I don't know about it:
> * Processor
> * Processor speed
> * Memory, memory type, size, are there any memory expansion slots?


RISC processor, 80 MHz, 128MB mem cannot be increased (soldered on), no expansion slots at all.


```
HR10-250-TiVo# cat /proc/cpuinfo
system type             : TiVo UMA P0 board
cpu model               : R5432 V3.0  FPU V1.0
BogoMIPS                : 161.79
cycle counter frequency : 81003906
HR10-250-TiVo# cat /proc/meminfo
        total:    used:    free:  shared: buffers:  cached:
Mem:  93495296 68960256 24535040        0  9457664 41639936
Swap: 133165056  4632576 128532480
MemTotal:        91304 kB
```
Almost like trying to get a 66 MHz Pentium-1 to display full-screen video at 30fps.



rlw said:


> If the OS resides on and boots from the hard drive, it seems to me that one could install another version of Linux on a hard drive and install that in the DirecTivo.


For commodity hardware, booting up a different version of Linux is straightforward. For custom hardware using nonstandard devices (like TiVo), you simply *must* get appropriate device drivers first. Such drivers are not available. Unless you are willing to reverse engineer the drivers yourself, it's not worth even starting on this project.


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## BTUx9 (Nov 13, 2003)

And that's for an hdtivo... for standard dtivos, the memory avail is <48MB


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## jporter12 (Mar 10, 2006)

Wow! Even more underpowered than I thought! I'm sure this has to do with cost, but might also be so that stuff like you're talking about can't be done!

I guess when running something like a TiVo, with dedicated hardware and software, you don't need much computing power, as it will all by optimized for the hardware, unlike a PC app, that has to run on multiple configurations, and doesn't need to be nearly as optimized.

I would like to see support for a USB mass storage device, although it's doubtful that will ever happen for the same reasons.


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## goony (Nov 20, 2003)

rlw said:


> Anyway, I still can't see why it's "impossible" to hack a DirecTivo into a more generic MythTV box, probably upgradeable at some point to handle ATSC/HD (if the processor can handle the load).


If you have enough time, money and skill you could modify a Yugo to run in the Daytona 500.


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## JWThiers (Apr 13, 2005)

that will put a chill down your spine, Yugo ... Daytona


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## jporter12 (Mar 10, 2006)

JWThiers said:


> that will put a chill down your spine, Yugo ... Daytona


It's bad enough having Toyota in there!


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## BTUx9 (Nov 13, 2003)

jporter12 said:


> I would like to see support for a USB mass storage device, although it's doubtful that will ever happen for the same reasons.


Are you sure it doesn't? The usb-storage module is there, and the rc.sysinit framework has code to mount upgrade media from it.


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## jporter12 (Mar 10, 2006)

BTUx9 said:


> Are you sure it doesn't? The usb-storage module is there, and the rc.sysinit framework has code to mount upgrade media from it.


No, I'm not sure, but I would need to learn more about linux to be able to get it to work.


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## classicsat (Feb 18, 2004)

Actually, the Series 2 platform has a 233 or 266 Mhz MIPS processor with 32MB RAM (in an SD-D-TiVo). USB is USB2.0. and the majority of disk space is Tivo's proprietary media storage system, not EXT2 or EXT3, or any other PC-Linux FS.

The rest is covered well, very custom hardware, not a PC, custom Linux OS, tivoapp (closed source BTW) does most of the work not done by the hardware (which the core of is the TiVo ASIC, which works with the tuners to "record" to HDD. It is not really practical to rewrite everything.


The Series 1 has a 54 Mhz PPC.


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## BTUx9 (Nov 13, 2003)

Actually, I'm pretty sure it's 133/166 MHz (see broadcom bcm7317), and ~48 MB of ram usable by the OS

not sure why the non-standard tivo partitions would enter into consideration... if the idea is to replace the tivo OS with something else, those would obviously be reformatted to something more usable (like ext2)


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## rlw (Mar 1, 2007)

Thanks for all the replies (even the one about racing a Yugo at Daytona!).

 Too bad that the hardware is so closed, come 2/17/2009, Ebay will be flooded with $10 Tivo-2's....

RLW


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## goony (Nov 20, 2003)

rlw said:


> Too bad that the hardware is so closed, come 2/17/2009, Ebay will be flooded with $10 Tivo-2's....


Eh, maybe not as many as you think... how many people record over-the-air -vs- from satellite or cable?


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