- arm-netbook - Mailman test

HDMI High-Frequency Layout: Timing
by Richard Wilbur 01 Aug '17

01 Aug '17

HDMI Layout Notes for EOMA68 Cards by Richard Wilbur Timing Now that we have a speed of propagation, let's figure out the timing constraints imposed by the HDMI standard to the level we plan to support--v1.4. The standard doesn't seem to be freely available so, thankfully, several manufacturers mention various timing constraints in their documentation. The maximum pixel clock frequency is revealed in Toradex' design guide. Max Frequency: (HDMI v1.0-1.2a) 825 MHz (165 MHz pixel clock) (HDMI v1.3-1.4) 1.65 GHz (340 MHz pixel clock)[3] For a transmitter, many impedance improprieties (mismatches) can be forgiven in the first quarter-wavelength of propagation. T(Pixel) = 1/(pixel clock) = 1/(340MHz) = 2.94ns wavelength = velocity * period = 150um/ps * 2940ps = 441mm = 17400mil quarter wavelength = wavelength / 4 = 4350mil So, while we will try to match the impedance of our traces (transmission lines) as carefully as possible to the characteristic impedance specified for the cable, until we get to 4.3 inches from the signal source the line driver should be able to squash most reflections on the leading edges (first quarter wavelength). Impedance still matters for proper signal levels, but more in the bulk sense. The problem we will first turn our attention to, then, is that of skew (differences in signal arrival time) usually most noticeably caused by differences in trace length. Several goals are outlined in the literature I reviewed: skew between the clock pair and any data pair, skew between any two pairs (both of these fall under what I would call "Inter-pair Skew"), and skew between the traces of a particular pair ("Intra-pair Skew"). Inter-pair skew: (Requirements for HDMI v1.4) clock-data skew: Δt <150ps[3] => Δl < v * Δt = 22mm ~= 870mil T(Pixel) = 1/(pixel clock) = 2.94ns Skew(Inter-Pair) < 0.20 * T(Pixel)[4][5] = 588ps => Δl < v * Δt = 88.2mm ~= 3470mil Chrontel suggests matching between any two pairs be within 100mil.[5] => Δl < 100mil => Δt < Δl / v = 2540um / (150um/ps) = 17ps Of these design parameters Chrontel's 100mil recommendation seems to be the most restrictive, but still not out of the realm of possibility and probably a good precautionary limit. With only 17ps of inter-pair skew we meet even much tighter skew timings. Having non-vanishing inter-pair skew seems to actually be beneficial for reducing Electro-Magnetic Interference (EMI) by avoiding simultaneous transitions on multiple lines. Indeed the standard seems to be designed to recover up to 5 bits of worst-case inter-pair skew.[6] (Half of the 10-bit pixel time.) A Texas Instruments (TI) employee specifically suggested to keep the clock pair longer than the data pairs.[7] Intra-pair skew: (Requirements for HDMI v1.4) Toradex: Δt < 5ps[3] => Δl < v * Δt = 0.75mm ~= 30 mil Chrontel, Texas Instruments: T(bit) = 0.1 * T(Pixel) = 294ps Skew(Intra-Pair) = 0.15 * T(bit)[4][5] = 44.1ps => Δl = v * Δt = 6.62mm ~= 261 mil (Chrontel suggests, without saying why, that matching between signals should be within 5mil.[5] Given the context and calculations above suggesting 261 mil for total, this should probably be 5mil skew per segment.) Intra-pair skew causes EMI.[8] One way to see this is to consider what we're trying to do by routing the differential signal on a differential pair of traces. The goal is to make the distance between the traces as small as possible and still maintain the differential impedance needed to match the rest of the transmission line. This reduces the size of the effective antenna. When the signals are propagating in parallel down this pair of traces the length of the effective dipole antenna is the distance between the two wavefronts. If the traces are parallel and equidistant from the source, the combined wavefront will be perpendicular to the traces and of minimal effective size. If a difference in distance from the source occurs between the traces, the combined wavefront will no longer be perpendicular to the traces and the effective size will be larger. Toradex' "Layout Design Guide" has a great treatment of problems and suggested solutions throughout section 6 "High-Speed Layout Considerations". Of particular interest here is section 6.7 "Length Matching", pp. 21-25. Section 6.8 "Signal Return Path", pp. 25-29, is of considerable related interest. Chamferred Corners (or Trace Bend Geometry) I'm glad to see you are already using 45 degree bends instead of 90 degree corners. This helps the corners maintain the proper impedance. When serpentine traces (meanders) are needed to attain certain lengths of a single-ended trace, make sure individual segment lengths are at least 1.5x the width of the trace. Also, the spacing between parallel segments of the same trace should be at least 4x the width of the trace.[9] Length Matching Differential pair signals should not propagate asynchronously over a distance greater than 15mm[10] = 590mil. Thus the compensation for length mis-matches should be placed as close to the mismatch as possible. Differential traces can be segmented by a connector, pad (component or IC), or via.[10][5] "Each segment of a differential pair connection needs to be matched individually."[10] Ideal serpentine trace geometry for equalizing differential traces consists of the following proportions: the spacing between traces in the meanders should not exceed twice the normal spacing, and the length of more widely spaced traces should not exceed three times the normal trace width.[10, see Figure 23] References: [3] Toradex, page 38 [4] TI, page 4 [5] Chrontel, page 5 [6] https://forum.allaboutcircuits.com/threads/hdmi-inter-intra-pair-skew-inter… [7] https://e2e.ti.com/support/interface/high_speed_interface/f/138/t/267205 [8] https://www.researchgate.net/publication/224650488_Effects_of_skew_on_EMI_f… [9] Toradex, page 17, Figures 12 & 13 [10] Toradex, pages 22-23 Bibliography: http://www.chrontel.com/media/Application%20Notes/AN-B026%20Rev0.2.pdf http://e2e.ti.com/cfs-file/__key/telligent-evolution-components-attachments… http://docs.toradex.com/102492-layout-design-guide.pdf

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HDMI High-Frequency Layout: Speed of Propagation
by Richard Wilbur 01 Aug '17

01 Aug '17

HDMI Layout Notes for EOMA68 Cards by Richard Wilbur Speed of Propagation First let's calculate the speed of electromagnetic wave propagation in a microstrip differential pair on our circuit board. Then we can use that speed to convert the timing tolerances of the HDMI standard into distance tolerances which will guide our priorities in routing the differential pairs. Electromagnetic waves travel at the speed of light. But since the electromagnetic fields of these signals extend between the conductors into both air and the FR-4 substrate of our printed circuit board (PCB), they will not travel at the same speed as if they were travelling through a vacuum. Speed of light in a vacuum: c = 3.00e8 m/s Speed of light in some other substance: v(wave travelling in substance) = c / sqrt(relative permittivity of substance) Since the electromagnetic waves in question propagate partly in air and partly in the PCB substrate (FR-4), we estimate their governing permittivity to be between that of air and FR-4. Speed of propagation for signals conducted in differential microstrip on the PCB: relative permittivity of FR-4 = 4.4 [1] relative permittivity of air = 1 v(in FR-4) = 3.00e8 / sqrt(4.4) = 1.43e8 m/s v(partly in FR-4, partly in air) ~= 3.00e8 / sqrt(4) = 1.5e8 m/s = 150um/ps[2] References: [1] https://en.wikipedia.org/wiki/FR-4 [2] Toradex, page 21 Bibliography: http://docs.toradex.com/102492-layout-design-guide.pdf

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HDMI High-Frequency Layout: Introduction
by Richard Wilbur 01 Aug '17

01 Aug '17

This is a discussion of the considerations when designing and executing a PCB layout containing high-frequency signal traces--specifically in this case HDMI. It is being published to the [arm-netbook] mailing list in several sections dealing with related topics. The original was created in Open Document Text and I have dumped it into Unicode Text in order to accommodate the mailing list. Please let me know if you have any trouble reading the format and I will attempt to remedy the problem. I am releasing the first two sections before I sleep--the remainder after I sleep.

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Re: [Arm-netbook] HDMI v1.4 Audio Return and Ethernet channels
by Andrew Bolin 01 Aug '17

01 Aug '17

> > so *i'm* not quotes considering it quotes - if it's there and there's > a linux kernel module it's there, people can compile it and use it. > > l. > Can't use it if the pin has no connection to the CPU! In the last screenshots I saw ( http://hands.com/~lkcl/eoma/a20_hdmi_review/scrn2.png ), pin 2 HEAC+ (ethernet/ARC) is not connected to anything. Pin 1 (HEAC- & HPD) does go somewhere, but it's of no use for these functions by itself. CEC does seem to be routed and is mentioned on the A20 info page. No SBC that I've seen actually uses these functions (unfortunately). - Andrew.

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HDMI v1.4 Audio Return and Ethernet channels
by Richard Wilbur 01 Aug '17

01 Aug '17

Luke, Have you considered using the Audio Return channel in HDMI v1.4 to send digital multi-channel sound back to the EOMA68-A20? How about the Ethernet channel (also in HDMI v1.4)? Does the processor support these? They are optional capabilities of HDMI v1.4 and I only ask because it would change the routing. Sincerely, Richard

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Rv: Update: 2.7.4 EOMA68-A20 Cards Arrived
by el_gallo_azul 31 Jul '17

31 Jul '17

I'd be happy enough to supply my own MicroSD card (in place of the TSSOP-48 NAND IC). 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Broadcom BCM2837 100% libre now ?
by Bill Kontos 31 Jul '17

31 Jul '17

Open firmware seems to be available here for a minimal boot. I have no idea if this is reverse engineered or provided by Broadcom, it seems like broadcom has at least released all the headers under some bsd-like license. The firmware here is gplv2+. https://github.com/christinaa/rpi-open-firmware Here is a report of someone booting using only the free firmware dated Jan 2017 while the most recent commits are from April. http://crna.cc/b/11 If I recall correctly the kernel driver was already open-sourced in 2014. The VC4 mesa driver made and upstreamed by a broadcom emploee here. I'm kind of confused since the vpu has to be used for the rpi to boot even if you don't want video acceleration, but this is an foss drm driver for the vc4 silicon only... what's going on with the part of the blob that used to do the initialization? https://github.com/anholt/mesa/wiki/VC4 And some documentation https://www.kernel.org/doc/html/latest/gpu/vc4.html Is this enough ? Or close to enough for a fully libre BCM2837 system to make it worth taking a look ? It seems like with the community around the rpi any bugs etc would be very easy to spot and squash in the future. I still don't know what's going on with the wifi in that SoC and I won't pretend that I understand everything I just wrote, but it certainly seems like there has been some movement from the "the 2mb userland blob does everything" stage. I found somewhere that board schematics still require an nda though.

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screwed up the Riki200 plotter design
by Luke Kenneth Casson Leighton 29 Jul '17

29 Jul '17

http://forums.reprap.org/read.php?177,767087,779977#msg-779977 ok so i screwed up. i didn't do a full force-analysis of the plotter design concept, and it was only when i tried turning each of the motors that i realised that with a double pulley system the force on one is double that of the other. with the two pulleys being separated by 320mm that means that just turning the motor *will* cause the X/Y-ends to "shear". this is... bad :) fortunately someone posted a few days ago that they have a concept which they've named "Edge-XY" - similar to CoreXY except the single X-Gantry (the horizontal bar of an "H") is replaced with *dual* X/Y (cross) rods. now, what's particularly fascinating about Edge-XY is that an important and previously under-appreciated design flaw of CoreXY is completely sorted! also very fortunately, the EdgeXY concept is very very similar to what i was trying for the Riki200 plotter concept... so i can convert over to EdgeXY with very little extra work. about 16 hours of re-printing parts but about... a week's worth of CAD design effort. which isn't too bad for correcting a major design cock-up :) i will try to work in the double-pulley system into the redesign: due to the fact that the belts are fixed onto the moving X/Y-ends of the EdgeXY it would be a 3x force multiplier not a 4x one, but also the forces (the pulleys) would be *on the same blocks* (separated by about 20mm) and would be force-balanced. made that mistake once already.... not doing it again :) l. --- crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68

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CNC milling of plastic lumber instead of 3D printing?
by Ricardo Wurmus 28 Jul '17

28 Jul '17

Heya, this idea is too late for the current batches of laptops, but I was wondering if it wouldn’t be easier and faster to mill the laptop plastic parts out of recycled blocks of plastic (“plastic lumber”) with a CNC mill. The advantages are as follows: * suitable plastic lumber can be made from a wider range of plastics than 3d printer filament * plastic lumber can be made from readily available plastic waste. HDPE from plastic bags make for cheap sturdy blocks of material. * a CNC mill cares much less about the melting point of the work piece during operation than a 3d printer * there are fewer concerns about material shrinkage at construction time, because the work piece isn’t partially liquid at any time of the CNC operations. * processing the work piece is faster because it doesn’t require as much motion as printing sturdy zig zag patterns. * even rather unsophisticated CNC mills can be used as the work piece is rather soft compared to the usual CNC mill work pieces such as aluminium. The most obvious disadvantages are: * there seem to be much fewer vendors of plastic lumber than there are vendors of high quality 3d printer filament * this approach isn’t quite as common, so it may be harder to find good advice from experienced people. What do you think? (I’m currently in the process of setting up a plastic recycling work space for my plastic lumber needs.) -- Ricardo GPG: BCA6 89B6 3655 3801 C3C6 2150 197A 5888 235F ACAC https://elephly.net

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Cell phone question
by Joseph Lira 24 Jul '17

24 Jul '17

Hello So I read in one of your updates about the raspberry zero phone, it sound really cool and for some time i wanted to get a smartphone but i see that they all have sort shelf lives meaning you buy the lastest samsung and it will get maybe updates for 2 years which at that point its viewed as obsolete, not to mention all the lock downs from the vendor/manufacture. I have looked at copperhead os but they still have the issue with shelf life 3 years tops, so im wondering what phone do you guys use? I just want a phone that let me listen to my music, use the gps without any ties, control the camera, some apps, that i can keep updating and patching until its truelly obsolete and all will still respecting my privacy, does such a phone exist?

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Re: [Arm-netbook] Cell phone question
by ronwirring＠Safe-mail.net 23 Jul '17

23 Jul '17

-------- Original Message -------- From: Joseph Lira <saitdude(a)hotmail.com> Apparently from: arm-netbook-bounces(a)lists.phcomp.co.uk To: "arm-netbook(a)list.phcomp.co.uk" <arm-netbook(a)list.phcomp.co.uk> Subject: [Arm-netbook] Cell phone question Date: Sun, 23 Jul 2017 18:03:37 +0000 > Hello > >does such a phone exist? I think a common phone will get lineageos compatible. By default lineageos comes with no google applications. If lineageos apart from that gives you enough privacy and security, I also would want to know?

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Re: [Arm-netbook] early access EOMA68 to hardware for parabola ARM maintainers?
by Vincent 21 Jul '17

21 Jul '17

Yes, unfortunately I did press "reply" without noticing I was sending it to you directly instead of the list. However, I did send another email to the list as reply just a few seconds later. Yes, I'm interested in the a20 pre-production boards. You can add me with the following details: Vincent, Germany, my-email-address On 07/20/2017 07:42 PM, Luke Kenneth Casson Leighton wrote: > --- > crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68 > > > On Thu, Jul 20, 2017 at 6:14 PM, Vincent <ml.eoma68(a)eml.cc> wrote: >> Hi everybody, > > you sent this to me only! > >> Please also add me to the early access list. >> >> Since the project is experiencing some delays and I would like to move >> on with my i.MX7 design, it would be really helpful to have an early >> version as reference. > > ... of the a20? edit this and add some contact details / identifying > info that i will be able to reach you by > http://rhombus-tech.net/allwinner_a10/ > > >> Thank you very much. >> >> Best regards, >> Vincent >> >> On 06/21/2017 08:46 PM, Luke Kenneth Casson Leighton wrote: >>> --- >>> crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68 >>> >>> >>> On Wed, Jun 21, 2017 at 7:23 PM, Andreas Grapentin >>> <andreas(a)grapentin.org> wrote: >>>> >>>> Hi Luke, >>>> >>>> On Tue, Jun 20, 2017 at 11:20:25AM +0100, Luke Kenneth Casson Leighton wrote: >>>>> when endeavouring to do an update there were two key conflicts, >>>>> related to udev, systemd and mesa-gl attempting to be upgraded. the >>>>> upgrade could therefore not proceed. >>>> >>>> could you give us access to the image you used? that would make it >>>> easier to find the issues. >>> >>> can do. one ironic thing: i cannot remember how i got eudev >>> installed! i.e. from which repo. >>> >>> 1.7gb upload... *shudder*. ok. i have space. it's going to take... >>> 10 hours @ 40k/sec. will get back to you in a a few days as i do not >>> expect it to complete first time (rsync is my best friend here). >>> >>>> However, due to some changes in arch, there is currently no clean >>>> upgrade path from 2016 images that does not require manual intervention. >>>> See here: >>>> https://www.archlinux.org/news/ca-certificates-utils-20170307-1-upgrade-req… >>> >>> yuck. >>> >>> ok. >>> >>> _______________________________________________ >>> arm-netbook mailing list arm-netbook(a)lists.phcomp.co.uk >>> http://lists.phcomp.co.uk/mailman/listinfo/arm-netbook >>> Send large attachments to arm-netbook(a)files.phcomp.co.uk >>>

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Existential 3D Printing Moments
by Neil Jansen 21 Jul '17

21 Jul '17

Hi, I'm reaching out to Luke Kenneth Casson Leighton. I recently read your latest update post on the Crowd Supply campaign for the EOMA68, titled: "Existential 3D Printing Moments". You mentioned that you needed help and/or advice on 3d printing for manufacturing. I have a lot of very specific experience here. I ran an open source project that required us to set up a 3D printer farm for manufacturing our first run of machines. I've lived in China while trying to get our project ready for mass manufacture. I have some advice for you, if you're willing to listen. I'd prefer to chat via video or audio, as there's so much to cover, I'd get carpal tunnel typing it all out. I'd be OK with summarizing the meeting minutes here afterwards, as to not exclude anyone else. I can meet pretty much any time regardless of time zone. Let me know either way. I've been following this project for quite a while (since the Slashdot AMA years ago), and I really want you guys to succeed. I missed the crowd funding round, but would still buy a few after they're fulfilled. Send me a direct email if you're interested in chatting. njansen1 at gmail dot com

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rhombus-tech.net 'Server not found'
by Richard Wilbur 19 Jul '17

19 Jul '17

Anybody else see rhombus-tech.net right now? I'm thankful I saved the images of the PCB I'm reviewing to the local computer. -- Richard

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Do you think when the new LTS kernel comes out,
by zap 15 Jul '17

15 Jul '17

that it will support a20 in the near future? whether linux libre or not? I was curious because you said the processor a20 doesn't support linux 4.9 am I right? In september, I plan to order one. This will determine how much I want it. I use devuan ascii currently so... yeah. I don't really know when you will make the 2nd revision or whatever you call it of eoma68/? ? meaning the processor you choose which I believe you said was the rk3388 right?

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Technoethical - a good-looking seller of HW with Libre SW & firmware (Technoethical holds RYF certification)
by dumblob 12 Jul '17

12 Jul '17

Hi, I just came across Technoethical (https://tehnoetic.com/ ) and was surprised by the range of libre products they sell. Technoethical is also RYF (https://ryf.fsf.org/ ) certified. Luke, it might be worth contacting them with EOMA notebooks. Cheers, -- Jan

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OT: What is maker geeks filament like
by David Niklas 08 Jul '17

08 Jul '17

Luke, You have mentioned the need for better quality PLA and I just noticed this deal: http://www.makergeeks.com/mafigrbag2kg.html Not that I'm about to buy, but do you know anything about this company? Thanks, David

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Potential new mali driver
by Bill Kontos 08 Jul '17

08 Jul '17

I just spotted this https://people.freedesktop.org/~cbrill/dri-log/?channel=lima&date=2017-06-23 It seems like there is a new person working on a driver for mali hardware, specifically the mali-400, and apparently it is an amd employee.

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Fwd: The PowerPC Notebook campaign has just started
by lkcl . 28 Jun '17

28 Jun '17

---------- Forwarded message ---------- Date: Wed, Jun 28, 2017 at 12:00 AM Subject: The PowerPC Notebook campaign has just started To: "lkcl ." <luke.leighton(a)gmail.com> Hi Luke, I know you are very busy with your EOMA68 Computing Devices, in any case, I ask you to share that we have started our Donation Campaign the PowerPC Notebook project, if you lake to share it and in case donate something your are welcome. https://www.powerpc-notebook.org/campaigns/electrical-schematics-notebook-p… Thanks

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thoughts, for the future or a late future,
by zap 28 Jun '17

28 Jun '17

but I think whenever you decide to make a new eoma68 laptop design, make it a 13 inch instead of 11 inch. aka, more space, means more durability heat-wise... This would be even more effective whenever you start making your own processors probably because then it wouldn't need to be as low This is one idea I just wanted to throw at ya, but another idea came to me, its just an idea of course, but a libertybsd based router would be ultra secure I bet. if it is possible I mean. ;) Libertybsd = openbsd without blobs ps, if you decide to make a processor from lowrisc, will it have 3d acceleration/support for the latest opengl? Those are my thoughts for now. Tell me what you think.

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Pangea Electronics
by pelzflorian (Florian Pelz) 27 Jun '17

27 Jun '17

Hi, I told someone about EOMA68. When they Google searched for “modular laptop“ in German, they got this: http://pangeaelectronics.com/EN/index.html I don’t know what you think of that or if they would care about EOMA. To me the Web site looks more like they are interested in vendor lock-in, but who knows. Regards, Florian

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3D Printering Idea
by Christopher Havel 26 Jun '17

26 Jun '17

Hey, Luke, is this article at all useful to you? http://hackaday.com/2017/06/24/hackaday-prize-entry-a-3d-printer-management… It looks like something you could fairly easily implement in such a way as to potentially speed up laptop part printing... the way I envision it, you have one printer for each part, and it just spits out one after another into, eg, an empty Tide or Fresh Step box. ...or maybe I'm daydreaming. You tell me :)

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FPGA video decoder
by David Niklas 26 Jun '17

26 Jun '17

Hello, Some time ago Luke et al was discussing using an FPGA to decode video but thought it too expensive. Well, not that this changes anything, but I found this little beauty wile looking at something else: https://alphamaxmedia.com/w/index.php?title=NeTV2 Sincerely, David

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Re: [Arm-netbook] early access EOMA68 to hardware for parabola ARM maintainers?
by Andreas Grapentin 25 Jun '17

25 Jun '17

Hi, to pick up this discussion again, Parabola has concluded that we will for the time being need only one preview card, and I will privately pay for it in full. following are the contact information for the hacker in question: Andreas Grapentin (me) <andreas(a)grapentin.org> Potsdam, Germany I can provide a complete address through a more private channel :) Best, Andreas -- ------------------------------------------------------------------------------ my GPG Public Key: https://files.grapentin.org/.gpg/public.key ------------------------------------------------------------------------------

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Re: [Arm-netbook] mali gpu reverse engineering lkcl may ignore
by Mike Leimon 24 Jun '17

24 Jun '17

On 06/23/2017 11:29 AM, Bill Kontos wrote: > On Fri, Jun 23, 2017 at 4:27 PM, David Niklas <doark(a)mail.com> wrote: > >> Now can we get back to how to do the reverse engineering itself? > Someone should suggest Luc to open a monthly patreon-styled donation > page for working on lima. If ARM is still as openly hostile as they appear to be towards reverse engineering of their GPU designs, I don't think that pursuing lima development is a very good option. I suspect that if development of the driver resumes, they will probably continue their horrible crusade against Luc and I don't want to see that happen to anybody. I think that if we are really trying to play the long game here, then that money would be better spent working towards the development of an open GPU design that we can can use in future risc-v SOCs. Perhaps another option that might be more amenable and rewarding for Luc. Would be to open a monthly patron-styled donation page not to develop lima drivers, but instead to work together with people like Jeff Bush (the main guy developming the Nyuzi GPGPU: https://github.com/jbush001/NyuziProcessor ). To me (and I haven't read into it much) it seems like, the focus thus far for the Nyuzi project is only on developing the GPGPU and not so much looking at it from the point of view of, how would we write a Linux driver for this device. I think if we focused some money on Luc (driver developer) and the Nyuzi (hardware developer) developers, then they might be more inspired to focus their efforts on producing a quality GPGPU and supporting drivers. Honestly, I think that working together with people who are openly developing a GPU design and who would probably be quite welcoming of assistance from Luc would be a much better situation for him than if he went back to trying to working on the lima driver. Perhaps a company like si-five ( https://www.sifive.com/ ) or the risc-v organization might even consider trying to sponsor a collaboration like this as having a good open GPU implementation would certainly be a boon to them in the future. Anyhow, that is my two cents. -Mike

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