Kawasaki 80C51 Computer Hardware User Manual


 
KS152JB Universal Communications Controller
Technical Specifications
Kawasaki LSI USA, Inc. Page 29 of 120 Ver. 0.9 KS152JB2
in auto-reload mode. In such a case the baud rate is given by
Mode 1,3 baud rate = 2
(SMOD - 5)
X Oscillator Frequency / (12 x [256 - TH1])
It is also possible to achieve very low baud rates by putting Timer 1 in Mode1 as a 16 bit timer and
enabling its interrupt. The Timer interrupt is used to reload the Timer 1 with a 16 bit value using
software methods. A list of commonly used baud rates and how they can be achieved is shown in
table 4
Table 7: Timer 1 generated commonly used Baud rates
Baud Rate fosc SMOD C/T Mode
Reload
Value
Mode 0 Max 1 MHZ 12 MHZ X X X X
Mode 2 Max 375K 12 MHZ 1 X X X
Modes 1,3 62.5K 12 MHZ 1 0 2 FFh
19.2 K 11.059 MHZ 1 0 2 FDh
9.6 K 11.059 MHZ 0 0 2 FDh
4.8 K 11.059 MHZ 0 0 2 FAh
2.4 K 11.059 MHZ 0 0 2 F4h
1.2 K 11.059 MHZ 0 0 2 E8h
137.5 11.059 MHZ 0 0 2 1Dh
110 6 MHZ 0 0 2 72h
110 12 MHZ 0 0 2 FEEBh