AN979 Datasheet, PDF (7/14 Pages) STMicroelectronics – DRIVING AN ANALOG KEYBOARD WITH THE ST7 ADC

DRIVING AN ANALOG KEYBOARD WITH THE ST7 ADC
Table 2. Key Values
KEY
no key
‘F’
‘E’
‘D’
‘C’
‘B’
‘A’
‘9’
‘8’
typical digital
value
0x3FF
0x3C0
0x37E
0x33D
0x303
0x2C2
0x27E
0x23D
0x200
lower digital
limit of KEY
0x3DF
0x38E
0x35E
0x31D
0x2E3
0x2A2
0x25E
0x21D
0x1E0
KEY
typical digital
value
lower digital
limit of KEY
‘7’
0x1C0
‘6’
0x17E
‘5’
0x13C
‘4’
0x0FB
‘3’
0x0BC
‘2’
0x080
‘1’
0x041
‘0’
0x000
0x1A0
0x15E
0x11C
0x0DB
0x09C
0x060
0x021
0x000
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