VNC1L SPI interface

[MMK]

Hello,
Has anyone got the spi interface of the VNC1L USB controller chip working. I need some software and pointers to prove my design.
Michael

[Martin Berriman]

Hi Michael,

I am using the VNC1L RS232 interface rather than the SPI interface so cannot comment directly on what you are doing but I have so far found a number of bugs in the VNC1L firmware.

I have reported my findings to FTDI and they have provided good rapid support. They have sent me and I have tried out newer firmware than they currently have on their website and at least one of the bugs I found has been fixed. I am expecting them to update the website firmware shortly but they are probably still working on the other bugs at the moment.

I'm using the VDIFF firmware but it is very similar to the VDAP firmware. The documentation for the VDAP firmware is currently more accurate than for the VDIFF firmware which has some undocumented behaviour (at least for the RS232 interface).

For completeness, at the time of posting, the versions on their website are:
VDAP 01.10 and 02.08
VDIFF 01.10
VDIFF Documentation V1.06
VDAP Documentation V1.07

[MMK]

Martin,
Thanks for that update. Might be good to keep in touch.
I did manage to get the VNC1L to print using P2, and using the UART interface (hyperterminal on a PC), using the latest (2.16) VDAP firmware.
Today, I did also manage to read the firmware version using the SPI innterface so I am pretty sure I have the hardware correct. There are no notes/code samples available for SPI.
Cannot get it to do anything on the P1 port either.
Cheers,
Michael. (mmk@tsm-controls.com)

[Tadi]

Hi Martin!

Could you help me please?

We have a project that maybe needs firmware modifying in VDAP firmware.
I just want to ask you how do you decompile the firmware code and find the bugs, or where do you get the source for the firmware? Coz we need some program to modify it.

All our respect is yours, if you cn help us, please give us some answers.

Thanks: Tadam & Daniel

[Martin Berriman]

Hi Tadam,

I think my post may have misled you. I do not have access to the source code of the firmware for the Vinculum device; I have simply used the ROM files that FTDI provide and found bugs with the operation.

Having identified bugs, I reported them to the support guys are FTDI and they responded very quickly (within a day) saying that they had checked and verfied the problem and they were working on a solution.

Why do you need the source for the firmware? - If you have a good suggestion for a change or an improvement then I suggest you tell the FTDI support guys about it; if they agree then it is possible they will implement it in a future release - at least that is what I have done.

Regards
Martin

[Guest]

Thanks for all, Martin!

The source is needed for the reason, that we watched both firmwares (VDAP and VDIF) on the FTDI site, and we can't find any solution of our problem.

We want to use flash disks on both USB ports, and we want to use UART/FIFO/SPI for command monitor port exclusively. If we're right the command monitor port at VDAP is always the VNC1L I/O port, but USB flash disk can only be used on port 2.

However, when in VDIF we connect any suitable USB device to Port 1, it will take precedence, and is detected, then it will be the command monitor port automatically.

So, all in one, we want a solution that can manage USB flash disks on both ports, besides we want to use VNC1L I/O port as command monitor port.

We can't find out, what suitable
USB device means? We don't know, if we connect a USB flash disk on port 1, will the port 1 take the role of the command monitor port? So, is the USB flash disk a suitable device?

And sorry if our questions are a bit beginner-like.

[devau]

Hi Michael

It took me more than 3 months to let "communicate" a PIC 16F628 with the SPI Interface of th VNC1L. First thing to know: Support of FTDI is really bad. Also the biggest thing is, that the SPI Interface description of this chip is faulty. If you look at the clock signal on page 9 Figure 6, you can see that the data is valid between the falling edge of the clock and should remain valid after the following rise of the clock. But it is *not*! You have to read out the data *before* you rise the clock. But the signal timing diagram on page 10 shows, that the data is valid after the *rising* edge of the clock, showed by the timing T7 (20 ns for data valid).
I reported this to FTDI 14 days ago, but I've got no answer!
Somehow then I managed to communicate with this chip. But I still get errors, because there's the next problem: The status register. Using its bits should help you to manage some kind of software handshaking. FTDI support told me, that RXF# and TXE# bits have the same meaning as described in the parallel interface section. Forget about that. If there's a response from the chip, the TXE always goes low, but this is confusing thing: TXE low means you *can* transmit now. If data output is done, the TXE bit goes high and remains high! No communication from the chip means you must not communicate to the chip too! So its function is inversed to the description. If the chip is idle, the status register always returns 0x12. And what about the IRQ bits of that register? There's absolutely no description available. If you ask FTDI for coding samples: Sorry, at the moment there's nothing available. So it's up to you to break your brains with this chip. In fact, the idea to release such a chip was really great. But with such a support, it won't last long. If you want to look how to sell chips these days, go to the Microchip site. They provide excellent support, excellent datasheets and a huge library of code examples. Why can't FTDI do the same? One good thing: If you use the RS232-Interface then everything works. But I have to use the SPI-Interface for our design, so RS232 is meaningless for me.
Devau

[Out of My League]

Hello all. I have two usb slave devices that I wish to have communictae with an rs232 device. I did some reaserch and discovered the vnc1l; which appears to do exactly that. However, all thier firmware does not exactly seem appropriate - seeing as what they have on their web sight deals mostly with the communication of one usb device with a usb mass storage device. What I need is for the vnc1l to convert the usb signals from my two usb devices into rs232. Is this even possibe, and if it is does there already exist firmware for such an application?

[Deveng]

Hello Devau !

I use VMUSIC1 modul now RS232. SPI also not working.
V2.16 firmware run.
SPI initializing sample routine necessary.How must begin.
How far have you got.

Thanks Deveng

[kazimanwar]

Want some help plz..i want to read a file that is already in a USB flash stick and send it to my MCU to display itz name n size, first of all,is VNC1L workz fine with ATMEL 89c51(if not plz tell any other compatible microcontroller for this task)...if yes..plz cud anyone help me over with this project...Plz..

[erusch]

Hi,
Has anyone tried to communicate between VNC1L and SPI-capable PIC with the hardware SPI of this one ?
Currently i'm looking at FTDI's example code for software SPI. Your previous comments will be usefull.

[Yass]

Hallo
I'm using VDIP1 modul for reading data from usb key, And wish to communicate via uart with this. My problem is on hyper terminal, when I type a character, it take 10 sc for displaying it on the screen. I think there's no communication between PC and vdip1. I have flow all the steps in datasheet for making communication but it doesn't word. could some help me please.
Thank.

[magestik]

[dbotkin]

Heck, I'd be thrilled to even get SERIAL to work. Mine's not communicating at all.

I have to agree with the earlier observation about Vinculum tech support being close to worthless. I reported a problem with the VDPS firmware... the response was that it was a known bug, and they apparently don't have any interest in fixing it. Unfortunately, not only is it a known bug, it's pretty close to being a show stopper.

I'm currently seriously re-evaluating my choice of the VNC1L. There has to be another solution out there. All I need to do is talk to a USB keyboard and FLASH drive.

[magestik]

For the moment, i gave up with the SPI interface, there's something wrong i don't know what.

I tried the USART interface, which cost me half a day :(
Using the USART of the PIC, i managed to send and receive basic info, such as the firmware version of the chip.

Still no reading from a keyboard, but i have to find .