Ok, those shematics on the TS web is a little bit obsolete.....
danjperron wrote:
>If you use a multimeter you will see that the HBEN of the max197 is
>connected to ISA_AD000 (pin 60 of the xilink's I.C.)
>
>This is on the TS-7200.
>
>This is why the code I sent yearlier increment the address+1 for the msb.
>
>Daniel
>
>
>
>--- In Jim Jackson <> wrote:
>
>
>>
>>
>>
>>On Wed, 1 Nov 2006, Per-Olof wrote:
>>
>>
>>
>>>Then I might comment your answer. I have checked the ts website,
>>>www.embeddedarm.com, and they have demo code for the internal adc. If
>>>you are aware of the TS code for Optional mounted MAX 197, I would
>>>
>>>
>to be
>
>
>>>pleased for that link or information. What I found on TS page is:
>>>
>>>
>EP9301
>
>
>>>on-board A/D converter sample code
>>><http://www.embeddedarm.com/downloads/samplecode/adc_72xx.tar.gz>
>>>(04-17-2006) however that does not help me in the end to get all 12
>>>bits of the external ADC.
>>>
>>>
>>Sorry but it's as simple as RTFM. It's in the ts7200 manual - "single
>>sample acquisition procedure" under the A/D Converter sections.
>>
>>The same manual entry also says "The conversion result is now available
>>at locations 0x10C0_0000 (LSB) and 0x10C0_0001 (MSB). A single word read
>>at 0x10C0_0000 can also be used." Howver this is from the Preliminary
>>TS-7200 DRAFT manual. I bought my board within a month of so of
>>Technologics releasing the product, back in 2004.
>>
>>Being essentially pragmatic, I coded as per the manual - got the
>>
>>
>results I
>
>
>>expected and have never checked the schematic in this area. However
>>schematics are produced by humans (there were faults in other
>>
>>
>areas), and
>
>
>>I believe Technologics do not claim the schematics is 100% complete - it
>>is there to give enough information to enable people to interface to the
>>product.
>>
>>I would why you are so worried by it? Have you used code to read the
>>values and found that you didn't get 12bits? Maybe your code was wrong?
>>
>>I suspect only Technologics staff can answer your specific
>>internals questions.
>>
>>
>>
>>>And yes, I have read your code on your page. You maybe can explain how
>>>you get the complete 12 bits from the optional max197 with just one
>>>read, when the chip has only 8 bits ports with no HBEN. It the Cirrus
>>>EP93xx doing some stuff in between or anything that I missunderstood?
>>>You say in your code, adc_read that the value is: sv=*adc_io_read;
>>>
>>>
>where
>
>
>>>the address point at adc_io_read=(unsigned short *)IOMMAP(0x10c00000).
>>>However reading this once would give the 8 bit of max197? The
>>>
>>>
>difference
>
>
>>>is that the internal ADC is possible to have all 12 bits read when
>>>
>>>
>it is
>
>
>>>interfaced.
>>>
>>>So question remains, what is done with HBEN on the external mouted
>>>MAX197, to get all 12 bits?
>>>
>>>
>>>/PO
>>>
>>>
>>>Jim Jackson wrote:
>>>
>>>
>>>
>>>>On Tue, 31 Oct 2006, Per-Olof wrote:
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>>Hello,
>>>>>
>>>>>I have concerns how to use all the 12 bits on the MAX197 ADC on
>>>>>
>>>>>
>TS-7200.
>
>
>>>>>According to the schematics the HBEN is not connected to any port or
>>>>>function, and terefore it would not be possible to select to bit
>>>>>
>>>>>
>8..11
>
>
>>>>>form the conversion. Either I can't find any register or writing to
>>>>>MAX197 that would enable the uppber bits.
>>>>>Is it possible to use all 12 bits, or is the board just printed
>>>>>
>>>>>
>for 8
>
>
>>>>>bit (and 8 channel)?
>>>>>
>>>>>
>>>>>
>>>>>
>>>>I thought Technologics had put out some demo code for accessing the
>>>>MAX197 on a ts7200???? Have you checked all the docs?
>>>>
>>>>As I've recently said on another thread on the MAX197 - you can check
>>>>out my adc_logger and adio software referenced from my ts7200
>>>>
>>>>
>webpage.
>
>
>>>>Jim
>>>>
>>>>
>>>>
>>----------------------------------------------------------------------------
>>
>>
>>>>HomePage: http://www.comp.leeds.ac.uk/jj
>>>>TS7200 Page: http://www.comp.leeds.ac.uk/jj/linux/arm-sbc.html
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>
>
>
>
>
>
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
--
''~``
( o o )
+--------------.oooO--(_)--Oooo.--------------+
| |
| Per-Olof Åström Tel: +46 733117197 |
| Teligent AB - Customer Solutions |
| www.teligent.se Umeå Office / Sweden |
| |
| .oooO |
| ( ) Oooo. |
+---------------------\ (----( )------------+
\_) ) /
(_/
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/ts-7000/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/ts-7000/join
(Yahoo! ID required)
<*> To change settings via email:
<*> To unsubscribe from this group, send an email to:
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
|