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An Schwob in the USA
Guest
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 Posted: Tue Oct 14, 2008 5:08 am Post subject: Re: Which arm7 dev board to buy? |
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It also depends where you are located. You can get Olimex Boards from
Sparkfun in the US at a better price and less shipping but if you are
not in the US, Olimex might be the lowest cost.
Other boards particularly for LPCs can be found at http://www.lpctools.com
and another overview of tools for the LPC2000 and other ARM micros at
http://www.lpc2000.com/tools
Cheers An Schwob |
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Mike Harrison
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| Posted: Tue Oct 14, 2008 7:58 pm Post subject: Re: XMOS XC-1 kits are shipping |
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On Tue, 14 Oct 2008 06:57:27 -0700 (PDT), Leon <leon355@btinternet.com> wrote:
| Quote: | On 13 Oct, 20:42, Eric Smith <e...@brouhaha.com> wrote:
Bob wrote about XMOS:
They seem far too fixated on doing everything in software, things like
ethernet where there is no point shoveling bytes in software if
hardware can take care of it.
Leon wrote:
They are supplying free libraries for all the usual peripheral
functions. Doing stuff like that in software is much cheaper than
using hardware, and easier in many ways.
Been there, done that, and it's not cheaper or easier when you
consider the overall system cost impact, not just the "benefit" of
leaving out the hardware block. That was the path Scenix/Ubicom went
down, calling it "virtual peripherals", and it was not very
successful. Ubicom has since added hardware for Ethernet, USB,
etc. to their most recent parts. The reality is that a hardware
Ethernet MAC costs less than the total system cost impact of the
software alternative.
Eric
Not if you have four 400 MIPS cores on the chip, each with 64 bits of
I/O, 64k of RAM, with 3.2 Gbit/s comms links between cores and 32
threads per core, with switching between threads in one clock. If the
software is free, it is a very cost-effective solution, especially as
the chips will be very cheap.
Leon
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How cheap? Have you seen any pricing info yet? |
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Leon
Guest
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| Posted: Thu Oct 16, 2008 7:32 pm Post subject: Re: XMOS XC-1 kits are shipping |
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On 14 Oct, 15:58, Mike Harrison <m...@whitewing.co.uk> wrote:
| Quote: | On Tue, 14 Oct 2008 06:57:27 -0700 (PDT), Leon <leon...@btinternet.com> wrote:
On 13 Oct, 20:42, Eric Smith <e...@brouhaha.com> wrote:
Bob wrote about XMOS:
They seem far too fixated on doing everything in software, things like
ethernet where there is no point shoveling bytes in software if
hardware can take care of it.
Leon wrote:
They are supplying free libraries for all the usual peripheral
functions. Doing stuff like that in software is much cheaper than
using hardware, and easier in many ways.
Been there, done that, and it's not cheaper or easier when you
consider the overall system cost impact, not just the "benefit" of
leaving out the hardware block. That was the path Scenix/Ubicom went
down, calling it "virtual peripherals", and it was not very
successful. Ubicom has since added hardware for Ethernet, USB,
etc. to their most recent parts. The reality is that a hardware
Ethernet MAC costs less than the total system cost impact of the
software alternative.
Eric
Not if you have four 400 MIPS cores on the chip, each with 64 bits of
I/O, 64k of RAM, with 3.2 Gbit/s comms links between cores and 32
threads per core, with switching between threads in one clock. If the
software is free, it is a very cost-effective solution, especially as
the chips will be very cheap.
Leon
How cheap? Have you seen any pricing info yet?
|
Not yet. They have said that they will cost as little as $1 each.
That's for the single-core chip, presumably. 400 MIPS for $1 isn't
bad!
Leon |
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Austin
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| Posted: Sat Oct 18, 2008 6:40 am Post subject: Re: low pass digital filter on a fixed point microcontroller |
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Hi Johnny,
Grest, It's an impressive simple filter!
But how can I choose d value given the sampling frequency Fs and expected
cut-off frequency Fc?
I guess there must be some formula like
d= Func( Fs, Fc) ?
Best Regards,
Austin
| Quote: | Johnny Chang wrote:
What is the easiest way to do this?
A simple lowpass filter could look like this in C:
float d = 8.0f;
float lowpassFilter(float sample) {
static float filtered = 0.0f;
filtered += (sample - filtered) / d;
return filtered;
}
where "d" (=1, 2, 3...) defines the cut-off frequency: the higher d, the
lower is the cut-off frequency. "sample" is the next incoming sample and
"filtered" is the output of the filter. You call lowpassFilter for each
incoming sample and it returns the filtered value.
If you use d=2^n, with n=0, 1, 2..., it is easy to implement it very
fast
and for fixed point numbers.
--
Frank Buss, fb@frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de
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Frank Buss
Guest
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| Posted: Sat Oct 18, 2008 8:30 am Post subject: Re: low pass digital filter on a fixed point microcontroller |
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Austin wrote:
| Quote: | Grest, It's an impressive simple filter!
But how can I choose d value given the sampling frequency Fs and expected
cut-off frequency Fc?
I guess there must be some formula like
d= Func( Fs, Fc) ?
|
I don't know, I would just simulate it:
http://www.frank-buss.de/filter/
(screenshot, if you don't have Java:
http://www.frank-buss.de/filter/screenshot.jpg )
The displayed dB value is the gain of the power of the signal. The
calculation is very brute force: it just runs the filter with 8 cycles of a
sine for each sine frequency and calculates the power of the signal for
each tested frequency.
--
Frank Buss, fb@frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de |
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LittleAlex
Guest
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| Posted: Mon Oct 20, 2008 6:07 pm Post subject: spam |
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| spam |
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Stevek34
Guest
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| Posted: Tue Oct 21, 2008 5:28 pm Post subject: Re: Microcontroller with QVGA or VGA LCD controller |
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| Quote: | "John Devereux" <jdREMOVE@THISdevereux.me.uk> skrev i meddelandet
news:87ve3io38l.fsf@cordelia.devereux.me.uk...
"bigredhdl" <chartley@cetac.com> writes:
Does anyone have any recommendations for microcontrollers with LCD
controllers for QVGA (320x240) or full VGA (640x480) displays?
I've found a few large devices (a ColdFire v3 device, and a number of
ARM9's from Atmel) that have LCD controllers supporting much larger
screens, but these are pretty big and fast microcontrollers, with
large
pin counts and needing sizeable external memories.
I'm hoping to find something a bit smaller and cheaper, and easier to
work with.
Stand-alone LCD controllers would be an alternative, if such a thing
exists these days.
Does anyone have recommendations if the display is monochrome?
[snip]
I wonder if it is possible to bit-bang a monochrome QVGA? Should be
possible if it is just the row the row clocking that needs to be
accurately timed (and not each pixel).
--
John Devereux
On an AT91SAM7SE or AT32UC3A you could use an SSC
in loopback mode to read from internal RAM , send it through the SSC
and then receive it back and write it to the LCD.
320 x 240 = 9600 bytes, so you can fit into the internal SRAM.
At 60 Hz, this is is 576 kB/s.
--
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may not be shared by my employer Atmel Nordic AB
|
What was the outcome of this? I am in a similar situation, having to drive
a QVGA with colour depth of 8bit. I am currently looking at the new
Coldfire V2 MCF52277 with integrated LCD controler.
Does anyone have any experience with this device? |
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Hans-Bernhard Bröker
Guest
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| Posted: Tue Oct 21, 2008 6:38 pm Post subject: Re: spam |
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robert bristow-johnson wrote:
| Quote: | actually, Tim, for those tightwads like me who use the free Google
Groups service, renaming the thread covers over the old thread title.
|
Except that's not what these silly bastards do. They don't "rename the
thread", because threads don't have names. Postings have subject lines,
and threads contain postings. And every newsreader on the planet makes
its own decisions about how to display threads and their subject lines.
| Quote: | and that is preferable since it removes the main advertizement tagline
from view
|
No, it doesn't. You guys are under the completely mistaken impression
that what _you_ see in Google groups were "the" view of a thread. Well,
it's not. The way you abuse everybody's USENET service to cover up for
Google's failure to provide anything resembling a working spam filter
makes things worse for everybody.
Google groups was bad enough even before you guys made it an excuse for
adding insult to injury on the SPAM front. |
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donald
Guest
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| Posted: Tue Oct 21, 2008 7:49 pm Post subject: Re: Microcontroller with QVGA or VGA LCD controller |
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| Quote: | Does anyone have any recommendations for microcontrollers with LCD
controllers for QVGA (320x240) or full VGA (640x480) displays?
Stand-alone LCD controllers would be an alternative, if such a thing
exists these days.
Does anyone have recommendations if the display is monochrome?
|
Epson replaced their SED1335 controller family with S1D13700F02.
Digikey carries them at:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=S1D13700F02A100-ND
This chip is 64-pin TQFP w/built in 32K memory.
Google S1D13700 for app notes and sample code.
donald |
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Ulf Samuelsson
Guest
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| Posted: Wed Oct 22, 2008 12:23 pm Post subject: Re: Microcontroller with QVGA or VGA LCD controller |
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"Stevek34" <steve.kedward@huntleigh-diagnostics.co.uk> skrev i meddelandet
news:k4mdnXL95Jd8V2DVnZ2dnUVZ_j-dnZ2d@giganews.com...
| Quote: | "John Devereux" <jdREMOVE@THISdevereux.me.uk> skrev i meddelandet
news:87ve3io38l.fsf@cordelia.devereux.me.uk...
"bigredhdl" <chartley@cetac.com> writes:
Does anyone have any recommendations for microcontrollers with LCD
controllers for QVGA (320x240) or full VGA (640x480) displays?
I've found a few large devices (a ColdFire v3 device, and a number of
ARM9's from Atmel) that have LCD controllers supporting much larger
screens, but these are pretty big and fast microcontrollers, with
large
pin counts and needing sizeable external memories.
I'm hoping to find something a bit smaller and cheaper, and easier to
work with.
Stand-alone LCD controllers would be an alternative, if such a thing
exists these days.
Does anyone have recommendations if the display is monochrome?
[snip]
I wonder if it is possible to bit-bang a monochrome QVGA? Should be
possible if it is just the row the row clocking that needs to be
accurately timed (and not each pixel).
--
John Devereux
On an AT91SAM7SE or AT32UC3A you could use an SSC
in loopback mode to read from internal RAM , send it through the SSC
and then receive it back and write it to the LCD.
320 x 240 = 9600 bytes, so you can fit into the internal SRAM.
At 60 Hz, this is is 576 kB/s.
--
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may not be shared by my employer Atmel Nordic AB
What was the outcome of this? I am in a similar situation, having to drive
a QVGA with colour depth of 8bit. I am currently looking at the new
Coldfire V2 MCF52277 with integrated LCD controler.
Does anyone have any experience with this device?
|
There are plenty of devices capable of driving a QVGA @ 8 bpp.
The AT91SAM9261 has enough RAM for a double buffered
framebuffer, drawing in internal RAM is much faster than drawing
in an external SRAM.
If you need Ethernet, then the AT91SAM9263 would be a good choice.
--
--
Best Regards,
Ulf Samuelsson
ulf@a-t-m-e-l.com
This message is intended to be my own personal view and it
may or may not be shared by my employer Atmel Nordic AB |
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tns1
Guest
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| Posted: Fri Oct 31, 2008 7:58 am Post subject: Re: Microcontroller with QVGA or VGA LCD controller |
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Stevek34 wrote:
| Quote: | "John Devereux" <jdREMOVE@THISdevereux.me.uk> skrev i meddelandet
news:87ve3io38l.fsf@cordelia.devereux.me.uk...
"bigredhdl" <chartley@cetac.com> writes:
Does anyone have any recommendations for microcontrollers with LCD
controllers for QVGA (320x240) or full VGA (640x480) displays?
|
The LPC247x supports STN, TFT at QVGA possibly larger. For monochrome it
would take away only a few % of the total BW. There are app notes and a
discussion forum at NXP. |
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tobidelbruck
Guest
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| Posted: Mon Nov 03, 2008 7:58 pm Post subject: Re: About EZ-USB FX2 Using external clock |
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| Quote: | I use Cypress EZ-USB FX2 for a data transmit system, FX2 in Slave
FIFO mode, with FPGA as the master. I write proogram to transmit data
from the PC to FX2.(direc is OUT)
The problem is , when I set IFCONFIG = 0xC3 in firmware, which means
Slave FIFOs executes on internal 48MHz clk source, it works well. but I
need to set IFCONFIG = 0x43, which means Slave FIFOs executes on
external clk source provied by FPGA through IFCLK pin, in this case, I
can not write data into FX2. why ? 6MHz clock already sent to the
IFCLK pin.
|
An earlier post "welcome to a nightmare world" just about sums it up with
the cypresss FX2 well-known weakness in monitoring capability which reduces
us to "debug by LED flashing".
In our case we wanted to use port D as output port pins and not as FD15-8.
So we followed the instructions to set all WORDWIDE=0 in the EPxFIFOCFG and
got no output on port D!
The solution was to ensure that the IFCLK input to the slave fifos was
actually driven from the internal source, at least for a cycle. In our
system, it is driven from a CPLD which is in turn clocked from CLKOUT. But
if the CPLD is not programmed yet (e.g. during firmware development) it
doesn't provide IFCLK. This is enough to prevent port D from becoming
GPIO.
Also FWIW, here is our TD_Init
void TD_Init(void) // Called once at startup
{
// set the CPU clock to 48MHz
//CPUCS = ((CPUCS & ~bmCLKSPD) | bmCLKSPD1) ;
CPUCS = 0x12 ; // 1_0010 : CLKSP1:0=10, cpu clockspeed 48MHz, drive
CLKOUT output pin 100 which clocks CPLD
/*
(from raphael berner: the clocking is as follows:
the fx2 clockes the CPLD by the CLKOUT pin (pin 100), and the CPLD clocks
the fifointerface on IFCLK, so in the firmware you should select external
clocksource in the FX2 for the slave FIFO clock source.
*/
IOC = 0x00;
IOA = 0x00;
IOE= 0x00; // set port output default values - enable them as outputs
next
OEA = 0x8b; // 1000_1011. PA7 LED, PA3: nResetCPLD, PA1: runCPLD, PA0:
tsReset
// port B is used as FD7-0 for 8 bit FIFO interface to CPLD
OEC = 0x0F; // now are cochlea and offchip DAC controls, before was
0000_1101 // JTAG, timestampMode, timestampTick, timestampMaster,
resetTimestamp
OED = 0xFF; // all bit addressable outputs, all WORDWIDE=0 so port d
should be enabled
OEE = 0xFF; // all outputs, byte addressable
// set the slave FIFO interface to 30MHz, slave fifo mode
// select slave FIFO mode with with FIFO clock source as external clock
(from CPLD).
// if the CPLD is not programmed there will not be any FIFO clock!
// if there is no IFCLK then the port D pins are never enabled as
outputs.
// start with internal clock, switch to external CPLD clock source at end
of TD_Init
SYNCDELAY;
IFCONFIG = 0xA3; // 1010_0011 // internal clock, 30MHz, drive clock
IFCLKOE, slave FIFO mode
SYNCDELAY; // may not be needed
// disable interrupts by the input pins and by timers and serial ports.
timer2 scanner interrupt enabled when needed from vendor request.
IE &= 0x00; // 0000_0000
// disable interrupt pins 4, 5 and 6
EIE &= 0xE3; // 1110_0011;
// Registers which require a synchronization delay, see section 15.14
// FIFORESET FIFOPINPOLAR
// INPKTEND OUTPKTEND
// EPxBCH:L REVCTL
// GPIFTCB3 GPIFTCB2
// GPIFTCB1 GPIFTCB0
// EPxFIFOPFH:L EPxAUTOINLENH:L
// EPxFIFOCFG EPxGPIFFLGSEL
// PINFLAGSxx EPxFIFOIRQ
// EPxFIFOIE GPIFIRQ
// GPIFIE GPIFADRH:L
// UDMACRCH:L EPxGPIFTRIG
// GPIFTRIG
//disable all ports A,C,E alternate functions
SYNCDELAY;
PORTCCFG = 0x00;
SYNCDELAY;
PORTACFG = 0x00; // do not use interrupts 0 and 1
SYNCDELAY;
PORTECFG = 0x00;
EP1OUTCFG = 0x00; // EP1OUT disabled
SYNCDELAY;
EP1INCFG = 0xA0; // 1010 0000 VALID+Bulk EP1IN enabled, bulk
SYNCDELAY;
EP2CFG = 0x00; // EP2 disabled
SYNCDELAY;
EP4CFG = 0x00; // EP4 disabled
SYNCDELAY;
EP6CFG = 0xE0; // EP6 enabled, in bulk, quad buffered
SYNCDELAY;
EP8CFG = 0x00; // EP8 disabled
SYNCDELAY;
REVCTL= 0x03;
SYNCDELAY;
FIFORESET = 0x80;
SYNCDELAY;
FIFORESET = 0x06;
SYNCDELAY;
FIFORESET = 0x00;
SYNCDELAY;
EP6AUTOINLENH=0x02;
SYNCDELAY;
EP6AUTOINLENL=0x00;
SYNCDELAY;
EP6FIFOCFG = 0x08 ; //0000_1000, autoin=1, wordwide=0 to automatically
commit packets and make this an 8 bit interface to FD
SYNCDELAY;
EP2FIFOCFG = 0x00 ; // wordwide=0
SYNCDELAY;
EP4FIFOCFG = 0x00 ;
SYNCDELAY;
EP8FIFOCFG = 0x00 ;
//set FIFO flag configuration: FlagB: EP6 full, flagC and D unused
SYNCDELAY;
PINFLAGSAB = 0xE8; // 1110_1000
SYNCDELAY;
cycleCounter=0;
// missedEvents=0xFFFFFFFF; // one interrupt is generated at startup,
maybe some cpld registers start in high state
LED=1; // turn on LED
clock=1; bitIn=0; latch=1; powerDown=0; // init biasgen ports and pins
EZUSB_InitI2C(); // init I2C to enable EEPROM read and write
initDAC();
JTAGinit=TRUE;
IT0=1; // make INT0# edge-sensitive
EX0=0; // do not enable INT0#
IT1=1; // INT1# edge-sensitve
EX1=0; // do not enable INT1#
// timer2 init for scanner clocking in continuous mode
T2CON=0x00; // 0000 0100 timer2 control, set to 16 bit with autoreload,
timer stopped
RCAP2L=0x00; // timer 2 low register loaded from vendor request.
RCAP2H=0xFF; // starting reload values, counter counts up to 0xFFFF from
these and generates interrupt when count rolls to 0
ET2=0; // disable interrupt to start
toggleVReset();
// now switch to external IFCLK for FIFOs
SYNCDELAY; // may not be needed
IFCONFIG = 0x23; // 0010_0011 // extenal clock, slave fifo mode
SYNCDELAY; // may not be needed
} |
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Aaron Gray
Guest
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| Posted: Fri Nov 07, 2008 9:37 pm Post subject: Re: CREDIT CARD SERVISES |
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"MEGAL" <megal47@yahoo.com> wrote in message
news:43cd6752-09e2-4284-a296-b9f7eb4d1b98@a29g2000pra.googlegroups.com...
| Quote: | CREDIT CARD SERVISES
http://creditcardservises.blogspot.com
|
The order of the day in this financial climate is a Debit card, get a debit
card !
Aaron |
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Jerry Avins
Guest
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| Posted: Mon Nov 10, 2008 7:35 am Post subject: Re: more off topic garbage by rhf aka Retired Halfassed Fool |
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saltyfishsa@gmail.com wrote:
| Quote: | Shortwave radio enthusiasts have a right to enjoy a newsgroup
which was established for them and is supposed to be dedicated to
shortwave radio information.
And they have a right to do so without wading through all the off
topic garbage you post and it isn't incumbent upon them to filter
obnoxious morons like you out, also many don't have the capability to
do so.
Start behaving like a responsible adult and filter yourself by posting
your nonsense in the appropriate newsgroups.
|
So keep your garbage out of microsoft.public.excel, comp.arch.embedded,
rec.nude, and comp.dsp.
--
Engineering is the art of making what you want from things you can get.
ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ |
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Raoul Fleckman
Guest
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| Posted: Thu Nov 13, 2008 5:31 pm Post subject: Re: Recommended GPL-Spice under linux ? |
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On 2008-11-13, problems@gmail <problems@gmail> wrote:
| Quote: | Please advise what/where I may test Spice under linux.
== TIA.
|
It's unlikely to be as mature as the packages suggested by the other
(wiser) posters, but i've found Gnucap :
http://www.gnu.org/software/gnucap/
to be very usable and sufficient for my relatively modest
(analog/filter) needs.
--
r |
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