TMP92CF30
2009-06-12
92CF30-469
(5)
SPI Transmit Data Register (SPITD)
The SPITD0 and SPITD1 registers are used for writing the transmit data.
SPITD0 Register
7 6 5 4 3 2 1 0
Bit
Symbol TXD7 TXD6 TXD5 TXD4 TXD3 TXD2 TXD1 TXD0
Read/Write R/W
Reset
State
0 0 0 0 0 0 0 0
SPITD0
(0830H)
Function
Transmit data bits [7:0]
15
14
13
12
11
10
9
8
Bit Symbol
TXD15
TXD14
TXD13
TXD12 TXD11 TXD10 TXD9 TXD8
Read/Write R/W
Reset
State
0 0 0 0 0 0 0 0
(0831H)
Function
Transmit data bits [15:8]
SPITD1 Register
7 6 5 4 3 2 1 0
Bit
Symbol
TXD7 TXD6 TXD5 TXD4 TXD3 TXD2 TXD1 TXD0
Read/Write R/W
Reset
State
0 0 0 0 0 0 0 0
Function
Transmit data bits [7:0]
SPITD1
(0832H)
15 14 13 12 11 10 9 8
Bit Symbol
TXD15
TXD14
TXD13
TXD12 TXD11 TXD10 TXD9 TXD8
Read/Write R/W
Reset
State
0 0 0 0 0 0 0 0
(0833H)
Function
Transmit data bits [15:8]
Figure 3.17.12 SPITD Register
This register is used for writing the transmit data. When this register is read, the
last-written data is read out. This register is overwritten if the next data is written with the
transmit FIFO being full.
Since the transmit data registers can contain data of up to four bytes, it can support write
operations that are performed by using four-byte instructions, such as the parallel
operation of the SPI and DMA.
When writing the data, the transmit data at the address 830 must always be the first to
be written.
There are several restrictions of the data writing methods (i.e., instructions to be used).
For more details, please refer to the following table.
UNIT-mode Transmission
(FIFO Disabled)
Sequential-mode Transmission
(FIFO Enabled)
Transmit Data
Write Size
Instruction
Example
1-byte
transmission
unit16
=
0
2-byte
transmission
unit16
=
1
1-byte
transmission
unit16
=
0
2-byte
transmission
unit16
=
1
1-byte write
ld (0x830),a
○
•
Prohibited
•
2-byte write
ld (0x830),wa
•
○
○
○
4-byte write
ld (0x830),xwa
•
•
○
○
○
: All data that are written by the CPU are transmitted.
•
: Invalid data are also transmitted along with the data written by the CPU.
Summary of Contents for TLCS-900/H1 Series
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