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Has anyone here had experience with interfacing the S912 to a MAX3100 through the SPI ? Any help would be appreciated. -Roger |
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MAX 3100 using SPI
Started by ●February 3, 2005
Reply by ●February 3, 20052005-02-03
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In a message dated 2/3/05 9:02:13 P.M. Eastern Standard Time, writes: Has anyone here had experience with interfacing the S912 to a MAX3100 through the SPI ? ================================= several mentions of max3100 on the avrfreaks.net board.... probably some c code so it should be useful.... use search function to find old messages.... |
Reply by ●February 4, 20052005-02-04
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Yes, been using them for some years. Any specific problem? I don't try and get large through put, via the MAX3100. I leave that to the CPU SCI's. But for the low data rate stuff, they are pretty easy to use. Let me know how I can help. Peter L. At 01:55 AM 4/02/2005 +0000, you wrote: >Has anyone here had experience with interfacing the S912 to a MAX3100 >through the SPI ? > >Any help would be appreciated. > >-Roger > > >Yahoo! Groups Links > > |
Reply by ●February 4, 20052005-02-04
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Hi Roger, I've sent you off list, some functions that I have used. I haven't looked at them for a while, but if you have any questions, just ask. Peter L. At 11:54 AM 4/02/2005 +0000, you wrote: >Peter: >Basically, I am just trying to get the thing to talk with the s912 >over the SPI. >Haven't gotten to the UART end, yet. >Have just been writing to the 3100's configuration register >and reading the status back. I have not been too successful. >I am going to try a couple of different approaches today, >and then I will send you a code fragment, if you don't mind >taking a look at it for me. >And by the way, I only need 2400 and 9600 baud throughput, which >the 3100 should handle fine. >(I am using two different 3100's, by the way) >Thanks, >-Roger > >--- In , Peter Lissenburg <peter@s...> wrote: > > Yes, been using them for some years. > > Any specific problem? > > I don't try and get large through put, via the MAX3100. I leave >that to the > > CPU SCI's. But for the low data rate stuff, they are pretty easy to >use. > > Let me know how I can help. > > Peter L. > > > > At 01:55 AM 4/02/2005 +0000, you wrote: > > > > > > >Has anyone here had experience with interfacing the S912 to a >MAX3100 > > >through the SPI ? > > > > > >Any help would be appreciated. > > > > > >-Roger > > > > > > > > > > > > > > > > > > > > > > > >Yahoo! Groups Links > > > > > > > > > > > > >Yahoo! Groups Links > > |
Reply by ●February 4, 20052005-02-04
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Peter: Basically, I am just trying to get the thing to talk with the s912 over the SPI. Haven't gotten to the UART end, yet. Have just been writing to the 3100's configuration register and reading the status back. I have not been too successful. I am going to try a couple of different approaches today, and then I will send you a code fragment, if you don't mind taking a look at it for me. And by the way, I only need 2400 and 9600 baud throughput, which the 3100 should handle fine. (I am using two different 3100's, by the way) Thanks, -Roger --- In , Peter Lissenburg <peter@s...> wrote: > Yes, been using them for some years. > Any specific problem? > I don't try and get large through put, via the MAX3100. I leave that to the > CPU SCI's. But for the low data rate stuff, they are pretty easy to use. > Let me know how I can help. > Peter L. > > At 01:55 AM 4/02/2005 +0000, you wrote: > >Has anyone here had experience with interfacing the S912 to a MAX3100 > >through the SPI ? > > > >Any help would be appreciated. > > > >-Roger > > > > > > > > > > > > > > > >Yahoo! Groups Links > > > > > > > > |
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Reply by ●February 4, 20052005-02-04
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rlewis51 wrote: > > Has anyone here had experience with interfacing the S912 to a MAX3100 > through the SPI ? > > Any help would be appreciated. > > -Roger Yes, I've done a couple cards which have three MAX3100 in addition to the two SCI ports, in the worst case all pounding full duplex 115200bps. Needless to say, there were some pretty hairy situations. Some because the MAX3100 datasheet is a bit ambiguous in places and misleading in others. Other problems were due to the numerous SPI errata and the one nice SCI errata in DP256B. But it works now, phew! Care to ask anything more specific? Sam |
Reply by ●February 4, 20052005-02-04
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Sam and Peter: Here's one of the symptoms that I am having: SPIF isn't being set. That tells me that the SPI is not getting a complete byte transfer from the 3100. A little about my glue logic: I am manually selecting the 3100 (actually, the 3110E, which is the same part plus a Max232)using one of the port pins on the micro. The SS line from the micro is not being used. Reading the (yes, Sam, it's ambiguous) 3110 document, I see that the first (15th) bit is presented at the falling edge of CS-. Since there is a finite (but small, since I am writing this in assembler) amount of time before assertion of CS- and the first SCLK cycle from the micro, I am wondering if the micro is not seing that first bit of the transfer from the 3110. -Roger --- In , Sam Laur <slaur@u...> wrote: > rlewis51 wrote: > > > > Has anyone here had experience with interfacing the S912 to a MAX3100 > > through the SPI ? > > > > Any help would be appreciated. > > > > -Roger > > Yes, I've done a couple cards which have three MAX3100 in addition to > the two SCI ports, in the worst case all pounding full duplex 115200bps. > Needless to say, there were some pretty hairy situations. Some because > the MAX3100 datasheet is a bit ambiguous in places and misleading in > others. Other problems were due to the numerous SPI errata and the one > nice SCI errata in DP256B. But it works now, phew! > > Care to ask anything more specific? > > Sam |
