ST92195C STMicroelectronics, ST92195C Datasheet - Page 156

• Manufacturer Part Number: ST92195C
• Description: 48-96 Kbyte Rom Hcmos Mcu With On-screen Display And Teletext Data Slicer
• Manufacturer: STMicroelectronics

TELETEXT SLICER AND ACQUISITION UNIT (Cont’d)
7.7.5.2 Hamming 8/4 Decoding
!bi is bi complemented.
A
B
C
D
Equation Number
A
0
0
0
0
1
1
1
1
1
other cases
B
0
0
1
1
0
0
1
1
1
C
0
1
0
1
0
1
0
1
1
= b7
= b7
= b5
= b7
D
0
0
0
0
0
0
0
0
1
1
b5
b3
b4
b6
more than 1 error
Interpretation
b
b
b
b
b
b
b
b
1
7
5
0
3
2
4
6
ST92195C/D - TELETEXT SLICER AND ACQUISITION UNIT
b1
b2
b3
b5
no error
erroneous
erroneous
erroneous
erroneous
erroneous
erroneous
erroneous
erroneous
b0
b1
b1
b4
b3
b2
Handling
corrected
corrected
corrected
corrected
accepted
accepted
accepted
accepted
accepted
rejected
Equation
b1
b0
( = xor)
! b
2 3
b
b
b
b
b
b
b
b
7
7
7
7
7
7
7
7
7
! b
b
b
b
b
b
b
b
b
2 2
5
5
5
5
5
5
5
5
5
! b
b
b
b
b
b
b
b
b
2 1
3
3
3
3
3
3
3
3
3
!b
2 0
b
b
b
b
b
b
b
b
1
1
1
1
1
1
1
1
1
ERR bit
156/249
0
0
0
0
0
0
0
0
0
1