Specifications

DATA SHEET QF4A512
Rev D4, Dec 07 33 www.quickfiltertech.com
Alternatively other user-specific information and/or formats can be stored in this area.
The user data is not copied into chip RAM at power up. Since direct reads from EEPROM are not usually possible there are two
methods to read/write the user data:
a) Using the SCRATCH registers. The 8 registers starting at address 001Dh can be used to transfer data 8 bytes at a time, using
the multi-byte transfer method described above.
b) Using the data RAM at startup. If the device is powered up in Configure mode all 128 bytes of user data can be block
transferred into the filter data RAM starting at address 1000h. Once the device enters Run mode this data will be overwritten
with the data output from the FIRs so this technique can only be used at startup.
12. CONTROL REGISTERS
12.1 Overview
Table 16. Control Register Map
Channel
4
Maintenance (9)
Configuration (31)
00C0
Run & Status (2)
Channel
3
Maintenance (9)
Configuration (31)
0090
Run & Status (2)
Channel
2
Maintenance (9)
Configuration (31)
0060
Run & Status (2)
0051
Channel
1
Maintenance (9)
0032
Configuration (31)
0030
Run & Status (2)
001D
Global Maintenance (19)
0011
Global Configuration (12)
0009
Run & Status (8)
0005
EEPROM Startup (4)
0000
High Level (5)
Note: Numbers in parentheses are the number of bytes allocated to each function.
The Control Registers are located in the first 256 bytes of address space as shown in the table. The QF4A512 can be configured to
automatically load these registers from EEPROM, with the exception of the first 7 bytes, at power up or after a reset.
It is strongly recommended that the configuration and filter coefficient data is set up using the Quickfilter Pro software. For applications
requiring reconfiguration on the fly it is suggested that complete configuration files, generated by the software, are stored in external
memory and loaded in full to the device. However, it may often be necessary to write individual commands to the device, for example to
switch between run and configure mode, or to turn on/off specific channels. To accomplish this, more detailed descriptions of register
functions can be found in the following paragraphs.