z8f1601 ZiLOG Semiconductor, z8f1601 Datasheet - Page 99

• Manufacturer Part Number: z8f1601
• Description: Z8 Encore!? Microcontroller With Flash Memory And 10-bit A/d Converter
• Manufacturer: ZiLOG Semiconductor

PS017609-0803
Transmitting Data using the Interrupt-Driven Method
5. Check the TDRE bit in the UART Status 0 register to determine if the Transmit Data
6. Write the data byte to the UART Transmit Data register. The transmitter automatically
7. To transmit additional bits, return to Step 5.
accept new data for transmission. Follow these steps to configure the UART for interrupt-
driven data transmission:
1. Write to the UART Baud Rate High and Low Byte registers to set the desired baud
2. Enable the UART pin functions by configuring the associated GPIO Port pins for
3. Execute a DI instruction to disable interrupts.
4. Write to the Interrupt control registers to enable the UART Transmitter interrupt and
5. Write to the UART Control 1 register to enable Multiprocessor (9-bit) mode functions,
6. Write to the UART Control 0 register to:
7. Execute an EI instruction to enable interrupts.
The UART is now configured for interrupt-driven data transmission. When the UART
Transmit interrupt is detected, the associated interrupt service routine (ISR) should per-
form the following:
8. Write the data byte to the UART Transmit Data register. The transmitter will
9. Clear the UART Transmit interrupt bit in the applicable Interrupt Request register.
10. Execute the IRET instruction to return from the interrupt-service routine and wait for
The UART Transmitter interrupt indicates the availability of the Transmit Data register to
register is empty (indicated by a 1). If empty, continue to Step 6. If the Transmit Data
register is full (indicated by a 0), continue to monitor the TDRE bit until the Transmit
Data register becomes available to receive new data.
transfers the data to the Transmit Shift register and transmit the data.
rate.
alternate function operation.
set the desired priority.
if desired.
–
–
–
automatically transfer the data to the Transmit Shift register and transmit the data.
the Transmit Data register to again become empty.
Set the transmit enable bit ( TEN ) to enable the UART for data transmission
Enable parity, if desired, and select either even or odd parity.
Set or clear the CTSE bit to enable or disable control from the receiver via the
CTS pin.
Z8F640x/Z8F480x/Z8F320x/Z8F240x/Z8F160x
Z8 Encore!
UART
®
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