New USB chip for fast FPGA bitstream download

[Antti Lukats]

New 3rd generation USB interface chip FT2232C
has special high speed sync serial modes that allow very fast 1Mbit+
downloads of FPGA configuration streams.

there are lots of FPGA boards that use similar feature with old
(second generation) FTDI chips, the new chip looks pretty much better
specially for FPGA designs as also interfacing to FPGA logic fabric
can be implemented more efficiently.

hope this is not out of topic, at least I was almost going to design a
similar FPGA board (with FT245BM as bootloader), now I would defenetly
use the FT2232C.

the chips seems to be very new, so the best is to search google on
FT2232C
at least one supplier promises samples from stock already.

antti

 

[Uwe Bonnes]

Antti Lukats <antti@case2000.com> wrote:
: New 3rd generation USB interface chip FT2232C
: has special high speed sync serial modes that allow very fast 1Mbit+
: downloads of FPGA configuration streams.

: there are lots of FPGA boards that use similar feature with old
: (second generation) FTDI chips, the new chip looks pretty much better
: specially for FPGA designs as also interfacing to FPGA logic fabric
: can be implemented more efficiently.

: hope this is not out of topic, at least I was almost going to design a
: similar FPGA board (with FT245BM as bootloader), now I would defenetly
: use the FT2232C.

: the chips seems to be very new, so the best is to search google on
: FT2232C
: at least one supplier promises samples from stock already.

Before you doing so, look around on www.comsec.com/usrp/

There already is a solution with the CY7C68013 and a cyclone for PC
configuration download and Usb communication with a complete toolchain.

The site seems not to be linked, so look also at
http://www.comsec.com/wiki
and
http://www.comsec.com/wiki?UniversalSoftwareRadioPeripheral

--
Uwe Bonnes bon@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt
--------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------

 

[Antti Lukats]

"Uwe Bonnes" <bon@elektron.ikp.physik.tu-darmstadt.de> wrote in message
news:bvgoec$p3u$1@news.tu-darmstadt.de...

Antti Lukats <antti@case2000.com> wrote:
: New 3rd generation USB interface chip FT2232C
: has special high speed sync serial modes that allow very fast 1Mbit+
: downloads of FPGA configuration streams.

Before you doing so, look around on www.comsec.com/usrp/

There already is a solution with the CY7C68013 and a cyclone for PC
configuration download and Usb communication with a complete toolchain.

The site seems not to be linked, so look also at
http://www.comsec.com/wiki
and
http://www.comsec.com/wiki?UniversalSoftwareRadioPeripheral

thanks this site is really interesting when you get into the non-linked
pages

well CY7C68013 is already "old player" in the field, and I sure know it,
my arguments for FT2232C are
* smaller package 48 vs 128 TQFP
* NO FIRMWARE
* NO DRIVERS (all free and available win+linux+mac)
* Cheaper

so depending what you are doing you have to choose.
in cases where today FT245BM is used as FPGA downloader
use of FT2232C would bring new advantages.

antti
PS I am actually not very much fan of FTDI
I would prefer to see the new functions of FT2232C in
http://www.silabs.com/products/microcontroller/interface.asp

or use
http://www.silabs.com/products/microcontroller/usb_matrix.asp
F320
as bootloader that is very tiny chip MLP28 and includes onchip USB clock
generator!!!
it mounts completly below the USB connector

 

[Eric Smith]

antti@case2000.com (Antti Lukats) writes:

New 3rd generation USB interface chip FT2232C
has special high speed sync serial modes that allow very fast 1Mbit+
downloads of FPGA configuration streams.

If they went to the trouble of designing a new generation USB-serial
chip with a high-speed sync mode, why didn't they make it capable
of at least 8 Mbps? :-(

 

[Pablo Bleyer]

"Antti Lukats" <antti@case2000.com> escribió en el mensaje
news:bvih81$6q8$07$1@news.t-online.com...

hm good question, I was going to say its not possible in FS mode, but
well
peak bitrate is 12M so the sync serial should be able to pass it through
at
full speed. Well I have to admit I havent fully checked out the precise
specs, so maybe its little more. Another thing is sustained average bit
rate, that is always way smaller than max peak bit rate. 1Mbit average bit
rate isnt so bad, but agree 8 would be better.

According to the datasheet, when the port is configured as a synchronous
FIFO (as the FT245) it uses the same prescaler as the UART configuration,
and it is capable of delivering 3Mbaud. (I guess the clock is derived
dividing the base oscillator frequency by 2). However, the FT2232C has a new
bit-bang interface at port A called MPSSE (Multi-Protocol Synchronous Serial
Engine), which is a JTAG/SPI lookalike + GPIOs configuration capable of
*5.6Mbits*.

The really nice thing about the FT2232C is that it has 2 configurable
ports, with enhanced overall features. We just finished designing a
programmer/debugger for one of our products
(http://www.embedded.cl/gallery/ARMermelator/) that uses one channel of the
FT2232 as muxed JTAG for ARM debugging and FPGA configuration, and the
second channel for serial communication (eg debug monitor and Flash
programming). The FT2232C also makes it easy to power the main board and
programmer through the USB's 5 volts, so it is really a 3-in-1 combo.

Regards.

--
PabloBleyerKocik /"But what... is it good for?"
pbleyer / -- 1968 Engineer at IBM's Advanced Computing
@embedded.cl / Systems Division, commenting on the microchip

 

[Antti Lukats]

"Eric Smith" <eric-no-spam-for-me@brouhaha.com> wrote in message
news:qhu12b9mtp.fsf@ruckus.brouhaha.com...

antti@case2000.com (Antti Lukats) writes:
New 3rd generation USB interface chip FT2232C
has special high speed sync serial modes that allow very fast 1Mbit+
downloads of FPGA configuration streams.

If they went to the trouble of designing a new generation USB-serial
chip with a high-speed sync mode, why didn't they make it capable
of at least 8 Mbps? :-(

hm good question, I was going to say its not possible in FS mode, but well
peak bitrate is 12M so the sync serial should be able to pass it through at
full speed. Well I have to admit I havent fully checked out the precise
specs, so maybe its little more. Another thing is sustained average bit
rate, that is always way smaller than max peak bit rate. 1Mbit average bit
rate isnt so bad, but agree 8 would be better.

I guess only non HS USB microcontroller that could configure FGPA with
highest bitrate (12Mbit bit peak) is the uPSD from www.st.com it has user
programamble PLD inside the usb microcontroller so if that is programmed for
continous shift, ah (I an blblabullshit) - any USB micro with SPI interface
would get better than 1Mbit peak config download rate.

antti

 

[Peter Wallace]

On Sun, 01 Feb 2004 10:46:19 -0800, Antti Lukats wrote:

"Eric Smith" <eric-no-spam-for-me@brouhaha.com> wrote in message
news:qhu12b9mtp.fsf@ruckus.brouhaha.com...
antti@case2000.com (Antti Lukats) writes:
New 3rd generation USB interface chip FT2232C has special high speed
sync serial modes that allow very fast 1Mbit+ downloads of FPGA
configuration streams.

If they went to the trouble of designing a new generation USB-serial
chip with a high-speed sync mode, why didn't they make it capable of at
least 8 Mbps? :-(

hm good question, I was going to say its not possible in FS mode, but
well peak bitrate is 12M so the sync serial should be able to pass it
through at full speed. Well I have to admit I havent fully checked out
the precise specs, so maybe its little more. Another thing is sustained
average bit rate, that is always way smaller than max peak bit rate.
1Mbit average bit rate isnt so bad, but agree 8 would be better.

I guess only non HS USB microcontroller that could configure FGPA with
highest bitrate (12Mbit bit peak) is the uPSD from www.st.com it has
user programamble PLD inside the usb microcontroller so if that is
programmed for continous shift, ah (I an blblabullshit) - any USB micro
with SPI interface would get better than 1Mbit peak config download
rate.

antti

If you dont mind just one more <$1 CPLD chip the USB245 will allow full
speed download (8 MBITS/sec or so) to a FPGA (either in parallel with a tiny
state machine to shift data out of the FIFO and into the FPGA or serial
with a shift register)

The CPLD is also nice if you want the FPGA to be configured without needing
the USB interface, as the CPLD can also function as a state machine to
generate the read command (03H) to a low cost(<$2.00 for 8 mbit) serial
flash chip for on card config storage...

Peter Wallace

 

[Pablo Bleyer Kocik]

"Antti Lukats" <antti@case2000.com> wrote in message news:<bvih81$6q8$07$1@news.t-online.com>...

hm good question, I was going to say its not possible in FS mode, but well
peak bitrate is 12M so the sync serial should be able to pass it through at
full speed. Well I have to admit I havent fully checked out the precise
specs, so maybe its little more. Another thing is sustained average bit
rate, that is always way smaller than max peak bit rate. 1Mbit average bit
rate isnt so bad, but agree 8 would be better.

According to the datasheet, when the port is configured as a
synchronous FIFO (as the FT245) it uses the same prescaler as the UART
configuration, and it is capable of delivering 3Mbaud. (I guess the
clock is derived dividing the base oscillator frequency by 2).
However, the FT2232C has a new bit-bang interface at port A called
MPSSE (Multi-Protocol Synchronous Serial Engine), which is a JTAG/SPI
lookalike + GPIOs configuration capable of *5.6Mbits*.

The really nice thing about the FT2232C is that it has 2 configurable
ports, with enhanced overall features. We just finished designing a
programmer/debugger for one of our products
(http://www.embedded.cl/gallery/ARMermelator/) that uses one channel
of the FT2232 as muxed JTAG for ARM debugging and FPGA configuration,
and the second channel for serial communication (eg debug monitor and
Flash programming). The FT2232C also makes it easy to power the main
board and programmer through the USB's 5 volts, so it is really a
3-in-1 combo.

Regards.

--
PabloBleyerKocik /"But what... is it good for?"
pbleyer / -- 1968 Engineer at IBM's Advanced Computing
@embedded.cl / Systems Division, commenting on the microchip

 

[Khim Bittle]

On 1 Feb 2004 14:46:49 -0800, pablobleyer@hotmail.com (Pablo Bleyer
Kocik) wrote:

"Antti Lukats" <antti@case2000.com> wrote in message news:<bvih81$6q8$07$1@news.t-online.com>...
hm good question, I was going to say its not possible in FS mode, but well
peak bitrate is 12M so the sync serial should be able to pass it through at
full speed. Well I have to admit I havent fully checked out the precise
specs, so maybe its little more. Another thing is sustained average bit
rate, that is always way smaller than max peak bit rate. 1Mbit average bit
rate isnt so bad, but agree 8 would be better.

According to the datasheet, when the port is configured as a
synchronous FIFO (as the FT245) it uses the same prescaler as the UART
configuration, and it is capable of delivering 3Mbaud. (I guess the
clock is derived dividing the base oscillator frequency by 2).
However, the FT2232C has a new bit-bang interface at port A called
MPSSE (Multi-Protocol Synchronous Serial Engine), which is a JTAG/SPI
lookalike + GPIOs configuration capable of *5.6Mbits*.

The really nice thing about the FT2232C is that it has 2 configurable
ports, with enhanced overall features. We just finished designing a
programmer/debugger for one of our products
(http://www.embedded.cl/gallery/ARMermelator/) that uses one channel
of the FT2232 as muxed JTAG for ARM debugging and FPGA configuration,
and the second channel for serial communication (eg debug monitor and
Flash programming). The FT2232C also makes it easy to power the main
board and programmer through the USB's 5 volts, so it is really a
3-in-1 combo.

Regards.

--
PabloBleyerKocik /"But what... is it good for?"
pbleyer / -- 1968 Engineer at IBM's Advanced Computing
@embedded.cl / Systems Division, commenting on the microchip

.... with the ft245bm i can do transfers at a real 1 mbyte/sec from my
win appl .. the 232 version is a bit slower .. KB