INTERNAL SPECIFICATIONS
119
4.6.3.4 Mode 3
4.6.3.4.1 Outline
Mode 3 is another 11-bit frame UART mode (with one start bit, eight data bits, one multi-
purpose data bit, and one stop bit). Whereas the baud rate is 1/64th or 1/32nd of the
fundamental oscillator frequency in mode 2, the mode 3 baud rate can be freely selected
according to the timer/counter 1 or timer/counter 2 setting. Apart from the ability to vary the
baud rate, mode 3 is identical to mode 2.
A block diagram of the serial port in mode 3 is shown in Figure 4-35, and the operational timing
chart is given in Figure 4-36.
4.6.3.4.2 Mode 3 baud rate
As in mode 1, the timer/counter 1 or timer/counter 2 overflow can be set as the baud rate clock
source in mode 3 by independent TCLK and RCLK setting for the transmit and receive
circuits.
Where the baud rate is determined by the timer/counter 1 overflow, baud rate is determined
by the overflow frequency and SMOD value according to the following equations.
B = f
TC1
×
2
1
×
(SMOD=0)
B = f
TC1
×
(SMOD=1)
16
1
16
1
Where B is the baud rate and f
TC1
is the timer/counter 1 overflow frequency.
When timer/counter 1 is used as a timer in auto reload mode (mode 2), the baud rate is
determined by the following equations.
B = f
OSC
×
256-D
TH1
1
×
(SMOD=0)
(SMOD=1)
12
1
2
1
×
16
1
×
B = f
OSC
×
256-D
TH1
1
×
12
1
×
16
1
where B is the baud rate, f
OSC
the fundamental oscillator (XTAL1·2) frequency, and D
TH1
the
TH1 contents (expressed in decimal).
Where the timer/counter 2 overflow serves as the baud rate clock source, the baud rate is
determined by the overflow frequency irrespective of the SMOD value.
When timer/counter 2 is used as a counter, the baud rate is determined by the following
equation.
B = f
T2
×
65536-D
RCAP2
1
×
16
1
where B is the baud rate, f
T2
the frequency of the clock applied to the T2 pin, and D
RCAP2
the
contents of R
CAP2L
and R
CAP2H
(expressed in decimal).
Or if timer/counter 2 is used as a timer, the baud rate is determined by the following way.
Содержание MSM85C154HVS
Страница 1: ...MSM80C154S MSM83C154S MSM85C154HVS USER S MANUAL...
Страница 8: ...1 INTRODUCTION...
Страница 9: ...MSM80C154S 83C154S 85C154HVS 2...
Страница 15: ...MSM80C154S 83C154S 85C154HVS 8...
Страница 16: ...2 SYSTEM CONFIGURATION...
Страница 17: ...MSM80C154S 83C154S 85C154HVS 10...
Страница 23: ...MSM80C154S 83C154S 85C154HVS 16 MSM80C154STS MSM83C154STS 44 Pin Plastic TQFP TQFP44 P 1010 0 80 K...
Страница 48: ...3 CONTROL...
Страница 49: ...MSM80C154S 83C154S 85C154HVS 42...
Страница 60: ...4 INTERNAL SPECIFICATIONS...
Страница 61: ...MSM80C154S 83C154S 85C154HVS 54...
Страница 197: ...MSM80C154S 83C154S 85C154HVS 190 5 INPUT OUTPUT PORTS...
Страница 198: ...INPUT OUTPUT PORTS 191...
Страница 220: ...INPUT OUTPUT PORTS 213...
Страница 221: ...MSM80C154 83C154 85C154 214 6 ELECTRICAL CHARACTERISTICS...
Страница 222: ...ELECTRICAL CHARACTERISTICS 215...
Страница 236: ...7 DESCRIPTION OF INSTRUCTIONS...
Страница 237: ...MSM80C154S 83C154S 85C154HVS 230...