User`s manual

Rabbit 4000 Designer’s Handbook rabbit.com 89
Appendix A: Supported Rabbit 4000
Baud Rates
This table contains divisors to put into TATxR registers. All frequencies that allow 57600 baud up to
30MHz are shown (as well as a few higher frequencies). All of the divisors listed here were calculated
with the default equation given on the next page.
Crystal
Freq. (MHz)
2400
baud
9600
baud
19200
baud
57600
baud
115200
baud
230400
baud
460800
baud
1.8432 23520a
a. Baud rate is not available at given frequency.
--
3.6864 4711510- -
5.5296 71 17 8 2 - - -
7.3728 95 23 11 3 1 0 -
9.2160 11929144---
11.0592 143 35 17 5 2 - -
12.9024 16741206---
14.7456 19147237310
16.5888 21553268---
18.4320 239 59 29 9 4 - -
20.2752 b
b. Baud rate is available with further BIOS modification.
65 32 10 - - -
22.1184 *7135115 2 -
23.9616 * 773812 - - -
25.8048 * 834113 6 - -
27.6480 * 894414 - - -
29.4912 * 954715 7 3 1
36.8640 * 119 59 19 9 4 -
44.2368 * 143 71 23 11 5 2
51.6096 * 167 83 27 13 6 -
58.9824 * 191 95 31 15 7 3