Z8F082ASH020SC Datasheet, PDF (113/244 Pages) Zilog, Inc. – Z8 Encore XP-R F08xA Series with eXtended Peripherals

Z8 Encore! XP^® F08xA Seriess
Product Specification
95
(BRG[15:0]) that sets the data transmission rate (baud rate) of the UART. The UART data
rate is calculated using the following equation:
UART Data Rate (bits/s)
=
----------S---y---s--t--e---m------C-----l-o---c---k-----F----r--e---q---u----e--n----c--y-----(--H----z---)----------
16 × UART Baud Rate Divisor Value
When the UART is disabled, the Baud Rate Generator functions as a basic 16-bit timer
with interrupt on time-out. To configure the Baud Rate Generator as a timer with interrupt
on time-out, complete the following procedure:
1. Disable the UART by clearing the REN and TEN bits in the UART Control 0 register
to 0.
2. Load the acceptable 16-bit count value into the UART Baud Rate High and Low Byte
registers.
3. Enable the Baud Rate Generator timer function and associated interrupt by setting the
BIRQ bit in the UART Control 1 register to 1.
When configured as a general purpose timer, the interrupt interval is calculated using the
following equation:
Interrupt Interval (s) = System Clock Period (s) ×BRG[15:0] ]
UART Control Register Definitions
The UART control registers support the UART and the associated Infrared Encoder/
Decoders. For more information about the infrared operation, refer to the Infrared
Encoder/Decoder chapter on page 104.
UART Transmit Data Register
Data bytes written to the UART Transmit Data register (Table 60) are shifted out on the
TXDx pin. The Write-only UART Transmit Data register shares a Register File address
with the read-only UART Receive Data register.
Table 60. UART Transmit Data Register (U0TXD)
BITS
7
6
5
4
3
2
1
0
FIELD
TXD
RESET
X
X
X
X
X
X
X
X
R/W
W
W
W
W
W
W
W
W
ADDR
F40H
PS024705-0405
PRELIMINARY
UART