
UART
MOTOROLA
MC68328 DRAGONBALL PROCESSOR USER’S MANUAL
8-5
interrupt sources. While the UART EN bit is low, the master clock to all UART blocks is dis-
abled, reducing power consumption to a minimum.
8.2.5 UART Control Register
This register controls the overall UART operation. This register resets to $0000.
UART ENABLE
This bit enables the UART. While this bit is low, the UART is disabled and in low-power
mode. While this bit is high, the UART is active. This bit resets to 0.
0 = UART disabled
1 = UART enabled
NOTE
When the UART is first enabled after cold reset, before enabling
interrupts, set the UART ENABLE and RX ENABLE bits and per-
form a word-read operation on the receiver register to initialize
the FIFO and character-status bits.
RX ENABLE
This bit enables the receiver block. While this bit is low, the receiver is disabled and the
receive FIFO is flushed. This bit resets to 0.
0 = Receiver disabled and receive FIFO flushed
1 = Receiver enabled
TX ENABLE
This bit enables the transmitter block. While this bit is low, the transmitter is disabled and
the transmit FIFO is flushed. This bit resets to 0.
0 = Transmitter disabled and transmit FIFO flushed
1 = Transmitter enabled
RX CLK CONT
Receiver Clock Control
This bit controls the receiver operating mode of the receiver. While low, the receiver is in
16x mode where it synchronizes to the incoming data stream and samples at the per-
ceived center of each bit period. While high, the receiver is in 1x mode where it samples
the data stream on each rising edge of the bit clock. This bit resets to 0.
0 = 16x clock mode
1 = 1x clock mode
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
UART
ENABLE
RX
ENABLE
TX
ENABLE
RX CLK
CONT
PARITY
EN
ODD
EVEN
STOP
BITS
8/7
GPIO
DELTA
ENABLE
CTS
DELTA
ENABLE
RX FULL
ENABLE
RX
HALF
ENABLE
RX RDY
ENABLE
TX
EMPTY
ENABLE
TX HALF
ENABLE
TX
AVAIL
ENABLE
ADDRESS: $(FF)FFF900
Reset Value: $0000
Figure 8-2. UART Control Register
Summary of Contents for DragonBall MC68328
Page 5: ...vi MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 25: ...Overview 1 14 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 45: ...System Integration Module 2 20 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 103: ...Parallel Ports 7 16 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 117: ...UART 8 14 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 127: ...SPI Master 10 6 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...