Tibbo DS10x0, Руководство по программируемому оборудованию

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333 Programmable Hardware Manual (PHM)
© Tibbo Technology Inc.
RX Length Registers
Address = &h004 (low byte) and &h005 (high byte); read-only
access
Low and high bytes of the length of received data awaiting readout from the RX
data buffer . The Tibbit sets these registers automatically, upon the completion of
the IR data recording.
Note that the data length is expressed in bytes (even though the logical unit of
data in the RX buffer is a 16-bit word).
Carrier Divider Registers
Address = &h006 (low byte) and &h007 (high byte); read/write
access
Low and high bytes of the carrier divider -- a value that corresponds to the
modulation frequency in the following manner:
Modulation_frq = 12Mhz / divider_value
How to use these registers:
·
When the IR data recording is conducted in the carrier mode ( command register ,
bit 4 = 0) then after the successful reception of an IR code the carrier divider
registers will contain the divider value for the measured carrier frequency. Your
program will need to save the measured divider value together with the recorded
data.
·
When the IR data recording is conducted in the no-carrier mode (command
register, bit 4 = 1) then your program must preset the carrier divider registers with
the correct value for the
expected carrier frequency.
·
Before transmitting the IR data, your program must preset the carrier divider
registers with the correct value for the
desired carrier frequency.
TX and RX Data Buffers
Address range = &h800 ~ &hFFF
There are two data buffers -- TX buffer and RX buffer. Each buffer's capacity is
2048 bytes or 1024 16-bit words.
Both buffers are mapped into the same address space. The TX buffer is accessed
with
write transactions , while the RX buffer is accessed with read transactions . It is
not possible to read from the TX buffer or write into the RX buffer.
The TX buffer stores the data prepared for transmission. Before the data
transmission, your program must store the data to be transmitted into the TX
buffer, beginning from address &h800. Your program must also set
TX length
registers to the length of prepared TX data (in bytes).
The RX buffer accumulates incoming IR data received in the cause of data
recording. After the IR data recording completes, this buffer will contain the
received data, aligned at address &h800.
RX length registers contain the length of
received data (in bytes).