Return-Path: X-Spam-DCC: paranoid 1233; Body=3 Fuz1=3 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_40_50,HTML_MESSAGE autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id u1HFiQ0K015482 for ; Wed, 17 Feb 2016 16:44:26 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1aW4Cm-0001y8-8a for rs_out_1@blacksheep.org; Wed, 17 Feb 2016 15:39:52 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1aW4Cl-0001xz-T5 for rsgb_lf_group@blacksheep.org; Wed, 17 Feb 2016 15:39:51 +0000 Received: from mail-wm0-f48.google.com ([74.125.82.48]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.86) (envelope-from ) id 1aW4Bl-00038k-G3 for rsgb_lf_group@blacksheep.org; Wed, 17 Feb 2016 15:39:50 +0000 Received: by mail-wm0-f48.google.com with SMTP id b205so161204221wmb.1 for ; Wed, 17 Feb 2016 07:38:34 -0800 (PST) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=9Hn71ub+HfZ6NF6A7p5HU1DmabN9/qyfUQc7gfgLVQQ=; b=CkVBIpteKDW3Z3Qk2Rkw/cPIfHcq0++ilpwnCiiirlzY3AxrOVu/KTJcw+QOU5fp7S IY/I2cCYqBPASnCQKw1nbSuf2KfPP7476fOStuAZl1SE6YpVo5JpM3K/tSwO3nLt0gnL 91vveZluCif/QyKxa0m/bWZxOi+Nfsf+LlBQdqfcTQf6LiloHDGkDGHDakbEVMUNfevi E1c+LOcXzkQFH5M5z7LSqu4AH7CNDCJ69uykSdQVMCTyeJX73l1Xp/1ng21W3t2DGpSP g5VGAOS47qen0Yc5NMru0JEp8hq1oubqJfvOpHxe76IJo98Rx8LqqUsT7suamQZTI478 Ct8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; bh=9Hn71ub+HfZ6NF6A7p5HU1DmabN9/qyfUQc7gfgLVQQ=; b=eXz/XUCzyttYkPMB1E/Gb20RlbgON15J7jwKjIJHL1U++fEFuY99AbeaUh1GnPfKqI JQBcBAz5kbeDgpmxJQXxZNS7Z4UdBbc6pCBZRHYOaMagg4vK1w2NEuwR9kLvWs1owkem cncMtxmb+IzOnCGyNluQl8Yi8sO0t/gdnvjXcEH83cQDMnjLnJ9Et4RATzSHiUOINXW5 vmiygFkcn0IILLhxZNAwcQyNwr9nv/IzlhF28tyACJIegk67Uz35N0fD/yLuYRsU98zt mhJMHROpJYQUd8uaQwIdiZzu4BWJZ5KsXtaf5BEJHCguSDXsHNwkFfGJEyfg7CP/T1Ep ZkRw== X-Gm-Message-State: AG10YOQ8vzPvQ8sf3gJ3ad1prAnu81O3EPfEO1eT/neDZk1TGfhmxmN/ZXzRYkIox2CkA4ei0ObOxHutPEpv3g== MIME-Version: 1.0 X-Received: by 10.28.32.147 with SMTP id g141mr25912591wmg.19.1455723468588; Wed, 17 Feb 2016 07:37:48 -0800 (PST) Received: by 10.28.187.213 with HTTP; Wed, 17 Feb 2016 07:37:48 -0800 (PST) In-Reply-To: References: <56BDED97.5060308@freenet.de> <56BE0364.6070503@gmx.net> <56BE1134.7060205@freenet.de> <56BE1D9E.6060200@freenet.de> Date: Wed, 17 Feb 2016 15:37:48 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org, rsgb_lf_group@yahoogroups.co.uk X-Scan-Signature: e21031ef48bbae1c5a8c64549547751e Subject: Re: LF: PIC-based GPSDO with A/D converter / supported serial baudrates ? Content-Type: multipart/alternative; boundary=001a113c8fd83c8cc9052bf90839 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-Scanned-By: MIMEDefang 2.56 on 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 6863 --001a113c8fd83c8cc9052bf90839 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Duh... Must be going doolally in old age. : 1MB/s at two bytes per sample will allow 50kHz sampling absolute max at 3 bytes per sample, 33kHz. 'jnt On 17 February 2016 at 15:30, Andy Talbot wrote: > Hit send too soon ................ > mutter, mumble........ > > The following results were obtained : > > Requested Frequency > Baud rate Generated > > 3M 146xxx (it wobbled) > 2M 975xxx (it varied) > 1M 500000 > 800k 400000 > 500k 250000 > 480k 240000 > > So it looks as if the FTDI Chip's FT232 family is eminently useable to 1= M > baud > > With a 12 bit A/D and some framing, for two bytes per sample, that means > you could send 0.5M Samples/ second > > 16 bit sampling plus framing will need three bytes, so call it 300kS/s > > > > Andy G4JNT > > > > On 17 February 2016 at 15:23, Andy Talbot wrote: > >> I've just made some tests on the FTDI232 chip at high baud rates. >> >> Using a custom routine written in PowerBasic (CC) , I used that >> language's own interpretation and interface to the driver to pass arbitr= ary >> baud rates to the chip. With the device set for 8 data, 1 stop bit an= d >> no parity, I repeatedly send the character 0x55 in a continuous loop. T= his >> pattern of bits, if sent contiguously (characters are sent LSB first) >> should therefore result in a square wave being generated at a frequency >> exactly equal to half the specified baud rate. >> >> The FTDI232 data sheet states that baud rates are determined based on a >> 3MHz input to a divisor of (N + M/8, where N =3D 2 to 16384, plus two sp= ecial >> cases on N =3D 0 and N =3D 1 for 3Meg and 1Meg rates respectively. Th= is >> setting is hidden from my application, and happens transparently based o= n >> the baud rate I specify beign passed to the driver via PowerBasic. >> >> The following results were obtained : >> >> Requested Frequency >> Baud rate Generated >> >> 1M 500000 >> 2M >> >> >> >> On 12 February 2016 at 17:59, Wolfgang B=C3=BCscher = wrote: >> >>> Thanks Andy. I wanted to keep it simple (but not necessarily stupid), b= y >>> using available hardware. In my case, the dreadful (and, most likely, >>> "faked") Prolific USB <-> RS232 adapter. >>> >>> >> >> > --001a113c8fd83c8cc9052bf90839 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Duh...
Must be=C2=A0going doolally in old a= ge. :

1MB/s at two bytes per sample will allow=C2= =A0 50kHz sampling absolute max
at 3 bytes per sample, 33kHz.

'jnt



On 17 February 2016 = at 15:30, Andy Talbot <andy.g4jnt@gmail.com> wrote:
Hit send too soon ......= ..........
mutter, mumble........

T= he following results were obtained :

Requested=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 Frequency
Baud rate= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 Generated

3M=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= 146xxx=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 (it wobbled)
2M=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 975xxx=C2=A0=C2=A0=C2=A0=C2=A0 (it = varied)
1M=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 5000= 00
800k=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 400000
500k= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0 250000
480k=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0240000

So it looks as if the FTDI C= hip's=C2=A0 FT232=C2=A0family is=C2=A0eminently useable to 1M baud

With a 12 bit A/D and some framing, for two bytes per= sample, that means you could send=C2=A00.5M Samples/ =C2=A0second

16 bit sampling plus framing will need three bytes, so cal= l it 300kS/s



Andy=C2= =A0 G4JNT



On 17 February 2016 at 15:23, Andy = Talbot <andy.g4jnt@gmail.com> wrote:
=
I've just made some tests on the FTDI232 chip=C2= =A0at high baud rates.

Using a custom routine=C2= =A0written in=C2=A0=C2=A0PowerBasic (CC) , I used that language's own i= nterpretation and interface to the driver to pass arbitrary baud rates to t= he chip.=C2=A0=C2=A0 With the device set for 8 data, =C2=A01 stop bit and n= o parity,=C2=A0I=C2=A0repeatedly send the character 0x55 in a continuous lo= op.=C2=A0 This pattern of bits, if sent contiguously (characters are sent L= SB first) =C2=A0should therefore result in a square wave being generated=C2= =A0at a=C2=A0frequency exactly equal to=C2=A0half the specified baud rate.<= /div>

The FTDI232 data sheet states that baud rates are = determined based on a 3MHz input to a divisor of (N + M/8, where=C2=A0N =3D= 2 to 16384, plus two special cases on N =3D 0 and N =3D 1 for=C2=A0 3Meg a= nd 1Meg rates respectively.=C2=A0=C2=A0 This setting is hidden from my appl= ication, and happens transparently based on the baud rate I specify beign p= assed to the driver via PowerBasic.=C2=A0

The fol= lowing results were obtained :

Requested=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 Frequency
Baud rate=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 Generated
=
1M=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 500000
= 2M



On 12 February 2016 at 17:59, Wolfgang B=C3=BCscher <= dl4yhf@freenet.de> wrote:
=20 =20 =20
Thanks Andy. I wanted to keep it simple (but not necessarily stupid), by using available hardware. In my case, the dreadful (and, most likely, "faked") Prolific USB <-> RS232 adapter. =C2=A0=C2=A0=C2=A0



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