Toshiba H1 Series - Manual (Page 321)

TMP92CZ26A
92CZ26A-318
(2) Baud rate generator
The baud rate generator is the circuit which generates transmission/receiving clock
and determines the transfer rate of the serial channels.
The input clock to the baud rate generator, φT0, φT2, φT8 or φT32, is generated by
the 6-bit prescaler which is shared by the timers. One of these input clocks is selected
using the BR0CR field in the baud rate generator control register.
The baud rate generator includes a frequency divider, which divides the frequency
by 1 or N + (16 − K)/16 to 16 values, determining the transfer rate.
The transfer rate is determined by the settings of BR0CR
and BR0ADD.
• In UART mode
When BR0CR = 0
The settings BR0ADD are ignored. The baud rate generator divides
the selected prescaler clock by N, which is set in BR0CK. (N = 1, 2, 3 ...
16)
When BR0CR = 1
The N + (16 − K)/16 division function is enabled. The baud rate generator
divides the selected prescaler clock by N + (16 – K)/16 using the value of N set in
BR0CR (N = 2, 3 ... 15) and the value of K set in BR0ADD
(K = 1, 2, 3 ... 15)
Note: If N = 1 or N = 16, the N + (16 − K)/16 division function is disabled. Clear
BR0CR to 0.
• In I/O interface mode
The N + (16 − K)/16 division function is not available in I/O interface mode. Clear
BR0CR to 0 before dividing by N.
The method for calculating the transfer rate when the baud rate generator is used is
explained below.
• In UART mode
Baud rate = ÷ 16
• In I/O interface mode
Baud rate = ÷ 2
Input clock of baud rate generator
Frequency divider for baud rate generator
Input clock of baud rate generator
Frequency divider for baud rate generator