p87lpc778 NXP Semiconductors, p87lpc778 Datasheet - Page 53

• Manufacturer Part Number: p87lpc778
• Description: Cmos Single-chip 8-bit 80c51 Microcontroller 128-byte Data Ram, 8 Kb Otp
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Table 51:
Table 52:
9397 750 12378
Product data
Timer Count
Timer Value
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Baud rates, timer values, and CPU clock frequencies for SMOD1 = 0
Baud rates, timer values, and CPU clock frequencies for SMOD1 = 1
Baud Rate
2400
0.2304
0.4608
0.6912
0.9216
1.1520
1.3824
1.6128
* 1.8432
2.0736
2.3040
2.5344
2.7648
2.9952
3.2256
Baud Rate
2400
0.4608
0.9216
1.3824
* 1.8432
2.3040
2.7648
3.2256
* 3.6864
4.1472
4.6080
8.15.7 Using Timer1 to generate baud rates
When Timer1 is used as the baud rate generator, the baud rates in Modes 1 and 3
are determined by the Timer1 overflow rate and the value of SMOD1. The Timer1
interrupt should be disabled in this application. The Timer itself can be configured for
either ‘timer’ or ‘counter’ operation, and in any of its 3 running modes. In the most
typical applications, it is configured for ‘timer’ operation, in the auto-reload mode (high
nibble of TMOD = 0010b). In that case the baud rate is given by the formula:
Tables
obtained using Timer1 as the baud rate generator.
Mode 1, 3 baud rate
4800
0.4608
0.9216
1.3824
* 1.8432
2.3040
2.7648
3.2256
* 3.6864
4.1472
4.6080
5.0688
5.5296
5.9904
6.4512
4800
0.9216
1.8432
2.7648
* 3.6864
4.6080
5.5296
6.4512
* 7.3728
8.2944
9.2160
51
and
52
9600
0.9216
* 1.8432
2.7648
* 3.6864
4.6080
5.5296
6.4512
* 7.3728
8.2944
9.2160
10.1376
* 11.0592
11.9808
12.9024
list various commonly used baud rates and how they can be
Rev. 01 — 31 March 2004
=
9600
* 1.8432
* 3.6864
5.5296
* 7.3728
9.2160
* 11.0592
12.9024
* 14.7456
16.5888
* 18.4320
CPU clock frequency / 192 (or 96 if SMOD 1 = 1)
------------------------------------------------------------------------------------------------------------------------ -
19.2 k
* 1.8432
* 3.6864
5.5296
* 7.3728
9.2160
* 11.0592
12.9024
* 14.7456
16.5888
* 18.4320
-
-
-
-
19.2 k
* 3.6864
* 7.3728
* 11.0592
* 14.7456
* 18.4320
-
-
-
-
-
256
–
CMOS single-chip 8-bit microcontroller
38.4 k
* 3.6864
* 7.3728
* 11.0592
* 14.7456
* 18.4320
-
-
-
-
-
-
-
-
-
TH 1
38.4 k
* 7.3728
* 14.7456
-
-
-
-
-
-
-
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© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
57.6 k
5.5296
* 11.0592
16.5888
-
-
-
-
-
-
-
-
-
-
-
P87LPC778
57.6 k
* 11.0592
-
-
-
-
-
-
-
-
115.2 k
* 11.0592
-
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