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Rockbox mail archiveSubject: H10/PP5020 - ADC and ScrollpadH10/PP5020 - ADC and Scrollpad
From: Anthony D'Alberto <afd1009_at_hotmail.com>
Date: Fri, 13 Jul 2007 09:50:01 -0400 Hello All, I've got a question or two about the pp5020/H10 player and the ADC scrollpad interface. 1.) Is there ANY more information about this chipset, and where would I find it? 2.) The ADCs are quoted on the datasheet as being 8 bit, but the ADC code says they are 10 bit. Are the 8 bit ADCs used as 10 bit ADCs through a feature of the chip? 3.) If the adc_data2 bits 0 and 1 contain lowest bits of the 10 bit A/D, then the code in adc_h10.c does not make sense to me: adc_data2 = (ADC_DATA2 >> (8*channel+6)) & 0x3. Shouldn't this be: adc_data2 = ADC_DATA2 >> (8*channel) & 0x3 or are the 2 lsb bits at the msb position of ADC_DATA2? I'm probably missing something very simple. 4.) Is there a way to drive the ADCs with interrupts or status registers? Of course my end goal is to get the scrollpad working the way the original firmware works. So I've noticed touching the scrollpad at the bottom has quite a bit more noise than touching the top. At the top, the noise will be +/- 0x08 - 0x10 whereas at the bottom it is somewhere near +/- 0x70. Also there seems to be a periodic dip in the value. This has made it really difficult to get the input data filtered. Any help would really be appreciated. I've looked at the iPod linux wiki memory map, and can't seem to relate it to the H10. For instance, does the H10 actually have access to the A/D converter interrupts? Thaks for any help. _________________________________________________________________ http://imagine-windowslive.com/hotmail/?locale=en-us&ocid=TXT_TAGHM_migration_HM_mini_2G_0507 Received on 2007-07-13 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |