AIS Baseband IC with/without RF Synthesiser
CMX7032/CMX7042
7.5.5 Read Data Registers
An array of four, 16 bit, C-BUS read registers form the Read Data C-BUS registers.
The device writes into these registers as instructed by the Data Task bits of the Command register while in
receive mode. The host µC can read these registers at any time except while a data task is in progress, in
which case the host µC should wait until the Data task complete bit is set in the Status register.
Data tasks access the registers as a number of words (1 to 4) or as a number of bits (1 to 16 in $A7),
however if a bit-format Data task is used it must be the final data task issued in a multi-data transfer to the
host. The next data task issued should be a DataWordResetN_Tx1/2 or DataBitResetN_Tx1/2 to re-
initialise the internal data buffer pointers (a bit-format task is usually used as the last transfer of a data
block that is not a complete number of words in length).
Word-format:
Bit:
Register $A9
Bit:
Register $AA
Bit:
Register $B8
Bit:
Register $B9
15
15
15
15
14
14
14
14
13
13
13
13
12
12
12
12
11
Data read from device to host µC word 1 (MSB Rx first)
11 10
Data read from device to host µC word 2 (MSB Rx first)
11 10
Data read from device to host µC word 3 (MSB Rx first)
11 10
Data read from device to host µC word 4 (MSB Rx first)
10
9
8
7
6
5
4
3
3
3
3
2
2
2
2
1
1
1
1
0
0
0
0
9
8
7
6
5
4
9
8
7
6
5
4
9
8
7
6
5
4
Bit-format:
Bit:
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Register $A9
Data read from device to host µC bits 0-15, (bit 15 received first)
7.5.6 Data Tasks
Data tasks are used to:
Load data from the Write Data registers into Data Buffers while in normal or configuration modes.
Load data from Data Buffers into the Read Data registers while in normal mode.
Load data from the Data Buffers to the DACs.
Read, write or operate subsystems by passing data using the Write Data and Read Data registers.
Table 4 Data Tasks
Name
Description
NULL
Null system task – takes no action.
DataWordReadN_Rx1
DataWordReadN_Rx2
DataWordWriteN_Tx
DataWordResetN_Rx1
Copy N words (1 to 4) from Rx1 data buffer to C-BUS Read Data registers.
Increment Rx1 data buffer pointer.
Copy N words (1 to 4) from Rx2 data buffer to C-BUS Read Data registers.
Increment Rx2 data buffer pointer.
Copy N words (1 to 4) from Write Data registers to Tx data buffer.
Increment data buffer pointer.
Reset Rx1 data buffer pointer to the top.
Copy N words (1 to 4) from Rx1 data buffer to Read Data registers.
Increment data buffer pointer.
Reset Rx2 data buffer pointer.
Copy N words (1 to 4) from Rx2 data buffer to Read Data registers.
Increment data buffer pointer.
Reset Tx data buffer pointer.
DataWordResetN_Rx2
DataWordResetN_Tx
Copy N words (1 to 4) from Write Data registers to Tx data buffer.
Increment the data buffer pointer.
Copy N bits (1 to 15) from Rx1 data buffer to Read Data register 0.
Increment the data buffer pointer.
Copy N bits (1 to 15) from Rx2 data buffer to Read Data register 0.
Increment data buffer pointer.
Copy N bits (1 to 15) from Write Data register 0 to Tx data buffer.
Increment data buffer pointer.
DataBitReadN_Rx1
DataBitReadN_Rx2
DataBitWriteN_Tx
2012 CML Microsystems Plc
32
D/7032/42_FI1.2/13
CMLMICRO [ CML MICROCIRCUITS ]
