Philips Semiconductors

Preliminary data

87LPC762

Low power, low price, low pin count (20 pin)

microcontroller with 2 kbyte OTP

2001 Oct 26

34

Table 10. Baud Rates, Timer Values, and CPU Clock Frequencies for SMOD1 = 1

Timer Co nt

Baud Rate

Timer Count

2400

4800

9600

19.2 k

38.4 k

57.6 k

115.2 k

–1

0.2304

0.4608

0.9216

* 1.8432

* 3.6864

5.5296

* 11.0592

–2

0.4608

0.9216

* 1.8432

* 3.6864

* 7.3728

* 11.0592

–

–3

0.6912

1.3824

2.7648

5.5296

* 11.0592

16.5888

–

–4

0.9216

* 1.8432

* 3.6864

* 7.3728

* 14.7456

–

–

–5

1.1520

2.3040

4.6080

9.2160

* 18.4320

–

–

–6

1.3824

2.7648

5.5296

* 11.0592

–

–

–

–7

1.6128

3.2256

6.4512

12.9024

–

–

–

–8

* 1.8432

* 3.6864

* 7.3728

* 14.7456

–

–

–

–9

2.0736

4.1472

8.2944

16.5888

–

–

–

–10

2.3040

4.6080

9.2160

* 18.4320

–

–

–

–11

2.5344

5.0688

10.1376

–

–

–

–

–12

2.7648

5.5296

* 11.0592

–

–

–

–

–13

2.9952

5.9904

11.9808

–

–

–

–

–14

3.2256

6.4512

12.9024

–

–

–

–

–15

3.4560

6.9120

13.8240

–

–

–

–

–16

* 3.6864

* 7.3728

* 14.7456

–

–

–

–

–17

3.9168

7.8336

15.6672

–

–

–

–

–18

4.1472

8.2944

16.5888

–

–

–

–

–19

4.3776

8.7552

17.5104

–

–

–

–

–20

4.6080

9.2160

* 18.4320

–

–

–

–

–21

4.8384

9.6768

19.3536

–

–

–

–

NOTES TO TABLES 9 AND 10:

1. Tables 9 and 10 apply to UART modes 1 and 3 (variable rate modes), and show CPU clock rates in MHz for standard baud rates from 2400

to 115.2k baud.

2. Table 9 shows timer settings and CPU clock rates with the SMOD1 bit in the PCON register = 0 (the default after reset), while Table 10

reflects the SMOD1 bit = 1.

3. The tables show all potential CPU clock frequencies up to 20 MHz that may be used for baud rates from 9600 baud to 115.2 k baud. Other

CPU clock frequencies that would give only lower baud rates are not shown.

4. Table entries marked with an asterisk (*) indicate standard crystal and ceramic resonator frequencies that may be obtained from many

sources without special ordering.