Rev 2.0 | SC5309A & SC5310A
Hardware Manual
SignalCore, Inc.
22
SC5309A & SC5310A Hardware Manual
4
Hardware Registers
The set of hardware registers of the downconverter may be divided into a configuration set and a
query set; the configuration registers are write-only registers to set up the states of the device, while
the query registers request the device to prepare and send back data associated with them. The
registers are identical for all communication interfaces: PXIe, USB, RS232, and SPI. Data
communication to all interfaces are sent in 1 byte wide, that is, data is transferred byte-by-byte.
Register data lengths vary in size, and it is important that the correct number of bytes are sent for the
corresponding register. Failure to do so may cause communication to lock-up and the device to
become unresponsive.
Configuration Registers
These are write-only registers to configure the device. The registers vary in length to reduce
redundant data and improve the communication speed, especially for SPI and RS232 interfaces.
Furthermore, it is vitally important that the length of data written to a register is exact because
failure to do so will cause the interfaces to misinterpret the incoming data, leaving the device in a
stalled state. The total number of bytes is the sum of the register address (1 Byte) and its
corresponding data bytes. For example, to set the RF frequency value, eight bytes must be written;
the sum of the 1 register byte and 7 data bytes. See the RF_FREQUENCY register of Table 4. The table
provides a summary of the configuration registers, and each register is explained in detail.
Table 4. Configuration Registers
Register Name
Reg Add
Serial
Range
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
INITIALIZE
0x01
[7:0]
Set to zeros [7:1]
Mode
SYSTEM_ACTIVE
0x02
[7:0]
Set to zeros [7:1]
Enable
“active”
LED
RF_FREQUENCY
0x10
[7:0]
Frequency Word (Hz) [7:0]
[15:8]
Frequency Word (Hz) [15:8]
[23:16]
Frequency Word (Hz) [23:16]
[31:24]
Frequency Word (Hz) [31:24]
[39:32]
Frequency Word (Hz) [39:32]
[47:40]
Frequency Word (Hz) [47:40]
[55:48]
Set to zeros
LO
IF_FREQUENCY
0x11
[7:0]
Frequency Word (Hz) [7:0]
[15:8]
Frequency Word (Hz) [15:8]
[23:16]
Frequency Word (Hz) [23:16]
[31:24]
Frequency Word (Hz) [31:24]
[39:32]
Frequency Word (Hz) [39:32]
[47:40]
Frequency Word (Hz) [47:40]
[55:48]
Set to zeros
RF_AMP
0x12
[7:0]
Set to zeros [7:1]
Enable
ATTENUATOR
0x13
[7:0]
0
Attenuator value
[15:8]
Set to zeros [15:11]
Attenuator Number
[23:16]
Set to zeros [23:16]
SIGNAL_PATH
0x14
[7:0]
If3
fil#2
select
If3 fil#1 select
IF2
filter
select
0
Bypass
IF3
conv
Ext. IF2
select
Bypass
convert
[15:8]
Set to zeros [15:10]
Rf amp
invert
