elecLear78
Member
I am trying to understand the following project
http://www.microchip.com/wwwAppNotes/AppNotes.aspx?appnote=en020394 . This is the application note for AN900 and also downloaded the source code. I am struck with the sine look up table which is provided in the source code
I have understood that from 270 degrees to 180 the sine values are negative and from 180 to 9o they are positive values and hence if i decode the hex values they are the complements for positive and negative values. My question is sin(270) is 1. Is it not required that the table should contain 1? Please help. Where exactly he is extracting 1 from the table.
http://www.microchip.com/wwwAppNotes/AppNotes.aspx?appnote=en020394 . This is the application note for AN900 and also downloaded the source code. I am struck with the sine look up table which is provided in the source code
Code:
TABLE code 0x0600 ;was 0x0100
;below table is from 270 degrees to 90 degrees @ 10 degree resolution; for 20MHz, PR2 = F9, Timer2 1:1 prescale
;sine_table db 0x00,0x02,0x08,0x11,0x1E,0x2E,0x40,0x54,0x69,0x80,0x96,0xAB,0xBF,0xD1,0xE1,0xEE,0xF7,0xFD,0xFF
;below table is from 270 degrees to 90 degrees @ 10 degree resolution; for 16MHz, PR2 = 137, Timer2 1:1 prescale
sine_table db 0x00,0x02,0x08,0x11,0x1E,0x2E,0x40,0x54,0x69,0x80,0x96,0xAB,0xBF,0xD1,0xE1,0xEE,0xF7,0xFD,0xFF
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