Fastwel CPC314, Руководство пользователя

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CPC314
C P C 3 1 4 U s e r M a n u a l
24
© 2 0 2 1 F a s t w e l V e r . 0 0 1
COM1 (RS-232): 0x3F8 / IRQ4, [115200 8,n,1]
7
COM2 (RS-232): 0x2F8 / IRQ3, [115200 8,n,1]
COM3 (RS-485): 0x3E8 / IRQ4, [115200 8,n,1]
COM4 (RS-485): 0x2E8 / IRQ3, [115200 8,n,1]
The exchange rate for serial ports can be set in the BIOS Setup. The exchange rate is determined
by the value of the CPU frequency divider register. The value of the divider and the data exchange
rate is calculated using the following formulas:
DIV = F / (16 • BR), BR=F / (DIV • SM))


F
– internal generator frequency, MHz (F = 1.8432 / 24 / 48);

DIV (divider)
– divider value (for F = 1.8432, 24 and 48 MHz – minimum value DIV = 1);

BR (baud rate) - required exchange rate, bit/sec;

SM (sampling mode)
– Base divider value (SM = 16).
Attention!
The receiver allows the exchange rate value downward bias by 3.0% and upward bias by 2.5%.
Table 1-7
– Frequency divider values for serial ports
Exchange
rate, bit/s
F=1.8432 MHz F=24 MHz F=48 MHz
Divider Error, % Divider Error, % Divider Error, %
300 384
–
5000
–
10000
–
600 192
–
2500
–
5000
–
1200 96
–
1250
–
2500
–
2400 48
–
625
–
1250
–
3600 32
–
417
–
625
–
4800 24
–
312
–
625
–
7200 16
–
208
–
417
–
9600 12
–
156
–
312
–
19200 6
–
78
–
156
–
38400 3
–
39
–
78
–
57600 2
–
26
–
52
–
115200 1
–
13
–
26
–
200000
– – – – – –
230400
– – – –
13
–
250000
– –
6
–
12
–
300000
– –
5
–
10
–
460800
– – – – – –
1 500 000
– –
1
–
2
–
______________________________________
7 The exchange rate is 115,200 bit/s, 8 bits, no parity check, 1 stop bit