TeleChips TCC720, User Manual

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TCC720
UART / IrDA
32-bit RISC Microprocessor for Digital Media Player
Dec. 16. 2002
Preliminary Spec 0.51
9 - 3
Receiver Buffer Register (RXD) 0x80000600
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
0
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 Received Data (when reading)
Whenever FRX flag of IR register is set, or RA flag of LSR register is set, reading of this register
gets the 1 byte of received data.
Transmitter Holding Register (TXD) 0x80000600
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
0
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 Transmitting Data (when writing)
When the transmission FIFO is not full, writing of this register fills that data to transmission FIFO.
Checking TF flag of LSR register can monitor the status of a transmission FIFO.
Divisor Latch Register (DL) 0x80000604
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Reserved
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Divisor Latch Value
This is for generation of the desired baud rate clock. This register is set to 0 at reset, UART is disabled
until this register is set by non-zero value. The value should be equal to (UART clock speed) / (16 * desired
baud rate). The UART clock is generated by clock generator block. It is recommended that the frequency
of UART clock is set to 3.6864MHz, so the desired baud rate can be acquired by writing (230400/baud
rate) to DL register.