PIC16F688
TABLE 10-2: REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Value on
all other
Resets
Value on:
POR, BOD
Addr
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
11h
BAUDCTL ABDOVF RCIDL
—
SCKP BRG16
—
WUE ABDEN -1-1 0-00 -1-1 0-00
0000 0000 0000 0000
12h
SPBRGH
SPBRG
Baud Rate Generator register, high byte
Baud Rate Generator register, low byte
13h
0000 0000 0000 0000
16h
TXSTA
RCSTA
CSRC
SPEN
TX9
RX9
TXEN
SREN
SYNC SENDB BRGH
CREN ADDEN FERR
TRMT
OERR
TX9D 0000 -010 0000 -010
RX9D 0000 000x 0000 000x
17h
Legend:
x= unknown, u= unchanged, — = unimplemented locations read as ‘0’. Shaded cells are not used by oscillators.
TABLE 10-3: BAUD RATES FOR ASYNCHRONOUS MODES
SYNC = 0, BRGH = 0, BRG16 = 0
BAUD
FOSC = 20.000 MHz
FOSC = 10.000 MHz
FOSC = 8.000 MHz
RATE
(K)
Actual
Rate
(K)
SPBRG Actual
SPBRG Actual
value
SPBRG
value
(decimal)
%
%
%
Error
value
Rate
(K)
Rate
(K)
Error
Error
(decimal)
(decimal)
0.3
1.2
—
—
—
255
129
31
15
4
—
—
—
129
64
15
7
—
1201
2403
9615
—
—
-0.16
-0.16
-0.16
—
—
103
51
12
—
1.221
1.73
0.16
1.73
1.73
8.51
-9.58
1.202
2.404
9.766
19.531
52.083
78.125
0.16
0.16
1.73
1.73
-9.58
-32.18
2.4
2.404
9.6
9.766
19.2
57.6
115.2
19.531
62.500
104.167
2
—
—
—
2
1
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 0
FOSC = 2.000 MHz
BAUD
RATE
(K)
FOSC = 4.000 MHz
FOSC = 1.000 MHz
Actual
Rate
(K)
SPBRG Actual
SPBRG Actual
value
SPBRG
value
(decimal)
%
Error
%
%
Error
value
Rate
(K)
Rate
(K)
Error
(decimal)
(decimal)
0.3
1.2
0.300
1.202
0.16
0.16
207
51
25
6
300
1201
2403
—
-0.16
-0.16
-0.16
—
103
25
12
—
300
1201
—
-0.16
-0.16
—
51
12
—
—
—
—
—
2.4
2.404
0.16
9.6
8.929
-6.99
8.51
—
—
19.2
57.6
115.2
20.833
62.500
62.500
2
—
—
—
—
—
8.51
0
—
—
—
—
—
-45.75
0
—
—
—
—
—
SYNC = 0, BRGH = 1, BRG16 = 0
FOSC = 10.000 MHz
BAUD
RATE
(K)
FOSC = 20.000 MHz
FOSC = 8.000 MHz
Actual
Rate
(K)
SPBRG Actual
SPBRG Actual
value
SPBRG
value
(decimal)
%
Error
%
%
Error
value
Rate
(K)
Rate
(K)
Error
(decimal)
(decimal)
2.4
9.6
—
—
—
129
64
2.441
9.615
1.73
0.16
1.73
-1.36
8.51
255
64
31
10
4
2403
9615
19230
55555
—
-0.16
-0.16
-0.16
3.55
—
207
51
25
8
9.615
0.16
0.16
-1.36
-1.36
19.2
57.6
115.2
19.231
56.818
113.636
19.531
56.818
125.000
21
10
—
DS41203B-page 82
Preliminary
2004 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
