PIC16C745/765
TABLE 11-3: BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 0)
4 MHz
6 MHz
24 MHz
Desired
Baud
Actual
Baud
% of
Error
Actual
Baud
% of
Error
Actual
Baud
% of
Error
SPBRG
SPBRG
SPBRG
300
300.48
1201.92
2403.85
4807.69
10416.67
20833.33
0.16
207
1200
2400
0.16
0.16
0.16
8.51
8.51
51
25
12
5
1201.92
2403.85
0.16
77
0.16
2.80
38
18
8
2403.85
4807.69
0.16
155
4800
4934.21
0.16
0.16
2.80
8.51
8.51
8.51
77
38
18
8
9600
10416.67
23437.50
46875.00
8.51
9615.38
19200
38400
57600
115200
230400
460800
921600
2
22.07
22.07
3
19736.84
41666.67
62500.00
125000.00
1
5
2
TABLE 11-4: BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 1)
4 MHz
6 MHz
24 MHz
Desired
Baud
Actual
Baud
% of
Error
Actual
Baud
% of
Error
Actual
Baud
% of
Error
SPBRG
SPBRG
SPBRG
300
1200
2400
1201.92
2403.85
4807.69
9615.38
19230.77
41666.67
62500.00
12500.00
0.16
207
0.16
0.16
0.16
0.16
8.51
8.51
8.51
103
51
25
12
5
2403.85
4807.69
0.16
155
4800
0.16
0.16
2.80
8.51
8.51
8.51
77
38
18
8
9600
9615.38
9615.38
19230.77
38461.54
57692.31
115384.62
250000.00
500000.00
0.16
155
77
38
25
12
5
19200
38400
57600
115200
230400
460800
921600
19736.84
41666.67
62500.00
12500.00
0.16
0.16
0.16
0.16
8.51
8.51
3
5
1
2
2
TABLE 11-5: REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Value on:
POR,
BOR
Value on all
other resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4 Bit 3 Bit 2
Bit 1
Bit 0
0000 -010
0000 -00x
0000 0000
0000 -010
0000 -00x
0000 0000
98h
18h
99h
TXSTA
CSRC TX9 TXEN SYNC
—
—
BRGH TRMT TX9D
FERR OERR RX9D
RCSTA SPEN RX9 SREN CREN
SPBRG Baud Rate Generator Register
Legend: x = unknown, -= unimplemented read as '0'. Shaded cells are not used by the BRG.
DS41124A-page 78
Advanced Information
1999 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
