Serial Console on THD.

[mrpenguin]

for 10$, and if you are not going to need more than one, it may be worth it. I bought bunch of Electrolytic capacitors, 1uf 50v polarized for cheap, a few max232 (not 'a' ver), and a bunch of 3.5mm jacks. I had the blank circuit board, wires, solder, etc. and a 4pin floppy power cable. Total spent was around 17$, but had the fun & satisfaction of creating it myself, and have enough parts for a few more if I find any other super deals on boxes.

My max232 have written on them:
Maxim
MAX232CPE
+0716

In my reading/research, if you use the max232a version, you may be able to use smaller or skip the capacitors, because they have within, but I really am not sure, it was a bit confusing, as you well know.

[AlphaWolf]

for 10$, and if you are not going to need more than one, it may be worth it.

Yeah I am only going to be using one, as I'll probably never have a second tivo hd (don't plan on it anyways.) I am thinking of removing that DB-9 port and soldering a 3.5mm port in its place, and see if I can mount this whole thing to the empty footprint below the holes in the back of the case. Assuming of course that what I linked is compatible with what I am trying to do here (again, not an electronics guru.)

Speak of those footprints, does anybody have any ideas on what they are the remnants of? I am wondering if one of those might have actually been where the 3.5mm port would have been mounted, but don't want to lift the motherboard out of the case just to find out as it wouldn't be helpful anyways.

[AlphaWolf]

If anyone is wondering for early bash, you need to insmod /platform/lib/modules/bcmtty_Gen06.o on TivoHD instead of bcm7315tty.o as in the 540's, and it uses ttyS1 not ttyS2.

Since you have to load a module for this to work, does that mean you can't enter the prom menu via this method? Otherwise I don't really understand why a module is needed if we already have tty communication before the kernel has even started to load (unless its just needed for bash to be able to accept incoming text from ttyS1?)

[Jamie]

Since you have to load a module for this to work, does that mean you can't enter the prom menu via this method? Otherwise I don't really understand why a module is needed if we already have tty communication before the kernel has even started to load (unless its just needed for bash to be able to accept incoming text from ttyS1?)

The PROM has code to support serial communications built in. The kernel needs a driver to support the hardware. It's the same as for other devices (disks, network, usb, etc). The drivers can either be built in, or external modules, but it needs a driver either way. The kernel does not use the PROM code to access the hardware, as it might in a PC with a BIOS (e.g. via software interrupts: link.)

If you load the tty module early (pre tivo rc.sysinit), make sure you tweak the startup scripts so that the tivo rc.sysinit continues after a module load failure, as described here.

[AlphaWolf]

So does this mean that after the prom is done doing its work, you lose all serial console output until the kernel module is loaded?

[mrpenguin]

No, you will still get the serial output, but no input/bash. Basically you can see but no talk. So you can see the error occur and the tivo reboot because of it, but you can't do anything to stop it.

The insmod, bash command line (and the failOk mod if loading early) are needed for the bash prompt and the ability to talk to the console.

[Dave20042004]

pinouts Nokia CA-42

TiVo HD pinouts labeled on the MB.

Had this CA-42 for awhile, now tying to get it to work, could use some advice:

I plan to cut off the Nokia proprietary connector end and solder the wires on a molex connector.

The pinout link above and it shows a pic of a 14 pin connector, 1, 2, 3, 5, 6, 7, 8. There is no 4 and no 9-14 labeled on pic.

From the chart, I want RX, TX and GND or 6, 7, and 8 respectively to attach to the TiVoHD serial connector.

My CA-42 has six pins. There is no space where 4 should be missing . Just six adjacent pins. CA-42.jpg
I labeled my pins 1-6 for ease. My question is:

Which of these six line up to RX, TX and GND respectively?

Thanks in advance,
Dave

[PlainBill]

You can't. The Nokia cable is for USB communications. The voltage, data rates, and handshake protocols are totally unlike the RS-232 the THD uses. What's more, the Nokia seems to be acting as a peripheral, not as a computer. so you can't even use a USB to RS-232 adapter.

PlainBill

[mike_s]

Had this CA-42 for awhile, now tying to get it to work, could use some advice:
Which of these six line up to RX, TX and GND respectively?

Here's some info on identifying the signals/wires.

[Dave20042004]

You can't. The Nokia cable is for USB communications. The voltage, data rates, and handshake protocols are totally unlike the RS-232 the THD uses. What's more, the Nokia seems to be acting as a peripheral, not as a computer. so you can't even use a USB to RS-232 adapter.

PlainBill

Bill
I am assuming this is the RS232 to TTL coverter claimed to work on the TiVoHD (Post #20 of this thread). Therefore, I wasn't clear. I plan to use a USB driver to get the serial output.
Dave

For those following later, I used Mike_S's link to determine that the pins that I labeled 4, 5 and 6 in my pic were in fact pins 6, 7, and 8 from the pinout diagram. After cutting off the end, there were three wires inside. With a DVM I found:
6 = Blue = Rx
7 = Red = Tx
8 = Orange = GND

Thanks Mike_S,
Dave

[Dave20042004]

I never made this clear in my last post but using the CA-32 cable has worked very well.... sort of:
I have the following two lines in my rc.sysinit.author:

tnlited 23 /bin/bash -login &
tivoftpd

1. I'm using minicom under Mint for my USB serial communications.
2. Starts blasting out information immediately during boot-up, works great!
3. Ends with "rc.sysinit complete", then nothing else.
4. I do not get a bash prompt, can't see my typing. Tivo is running fine.
5. I telnet in from the terminal using ethernet and get my bash prompt.

Now, when I mucked up my drive (presumably bad backup), the data still blasted out immediately for a few seconds but then asks for "password". The wierd thing is that I can type in and see my text at this time. (btw, p/w = "factory" does not work)

I suspect my "tnlited 23 /bin/bash -login &". Any suggestions?

Thanks in advance,
Dave

[tivo4mevo]

I never made this clear in my last post but using the CA-32 cable has worked very well.... sort of:
I have the following two lines in my rc.sysinit.author:

tnlited 23 /bin/bash -login &
tivoftpd

4. I do not get a bash prompt, can't see my typing. Tivo is running fine.
5. I telnet in from the terminal using ethernet and get my bash prompt.

This is because the lines you added above start only telnet and ftp, and I believe that you also desire to have bash running on the serial port. In which case, you need to add something like this

exec /bin/bash --login </dev/ttyDSS >/dev/ttyDSS&

to your start up scripts.

Now, when I mucked up my drive (presumably bad backup), the data still blasted out immediately for a few seconds but then asks for "password". The wierd thing is that I can type in and see my text at this time. (btw, p/w = "factory" does not work)

I suspect my "tnlited 23 /bin/bash -login &". Any suggestions?

What you describe here does sound like a bad disk image. The "password" prompt is the boot ROM (which runs before booting a kernel from the hard disk), so you might want to try restoring from a known good image, or perhaps inspecting the drive from a PC (e.g., bootpage, pdisk, tivopart, etc.) to see if it looks okay.