Philips Semiconductors
Preliminary data
Low power, low price, low pin count (20 pin)
microcontroller with 4 kbyte OTP
87LPC764
Table 10. Baud Rates, Timer Values, and CPU Clock Frequencies for SMOD1 = 1
Baud Rate
Timer Count
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
3.4560
* 3.6864
3.9168
4.1472
4.3776
4.6080
4.8384
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
6.9120
* 7.3728
7.8336
8.2944
8.7552
9.2160
9.6768
9600
0.9216
19.2k
38.4k
57.6k
115.2k
–1
–2
* 1.8432
* 3.6864
5.5296
* 11.0592
* 1.8432
2.7648
* 3.6864
* 7.3728
* 11.0592
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–3
5.5296
* 11.0592
16.5888
–4
* 3.6864
4.6080
* 7.3728
* 14.7456
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–5
9.2160
* 18.4320
–6
5.5296
* 11.0592
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–7
6.4512
12.9024
–8
* 7.3728
8.2944
* 14.7456
–9
16.5888
–10
–11
–12
–13
–14
–15
–16
–17
–18
–19
–20
–21
9.2160
* 18.4320
10.1376
* 11.0592
11.9808
12.9024
13.8240
* 14.7456
15.6672
16.5888
17.5104
* 18.4320
19.3536
–
–
–
–
–
–
–
–
–
–
–
NOTES TO TABLES 9 AND 10:
1. Tables 6 and 7 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 6 shows timer settings and CPU clock rates with the SMOD1 bit in the PCON register = 0 (the default after reset), while Table 7
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 115.2k 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.
33
2001 Oct 26
NXP [ NXP ]
