Struck Documentation
SIS3153
VME interface
Page 8 of 38
3.2 USB Register description
The function of the individual registers is described in detail in this section.
The first line after the subsection header (in Courier font) like:
#define SIS3153_CONTROL_STATUS 0x0
refers to the sis3153usb.h header file.
3.2.1 USB Control/Status Register(write/read)
#define SIS3153USB_CONTROL_STATUS
0x0
The control register is in charge of the control of some basic properties of the SIS3153 board,
like enabling Led test mode. It is implemented via a selective J/K register, a specific function
is enabled by writing a 1 into the set/enable bit, the function is disabled by writing a 1 into the
clear/disable bit (which location is 16-bit higher in the register). An undefined toggle status
will result from setting both the enable and disable bits for a specific function at the same
time.
On read access the same register represents the status register.
Bit
write Function
read Function
31
reserved
0
30
reserved
0
29
reserved
USB speed flag bit 1
28
reserved
USB speed flag bit 0
27
reserved
0
26
reserved
0
25
reserved
0
24
reserved
0
23
reserved
0
22
reserved
0
21
reserved
0
20
Clear SPI-Flash interface reset (*)
0
19
Clear USB internal access control bit 1 (*)
0
18
Clear USB internal access control bit 0 (*)
0
17
Clear Led test mode (*)
0
16
Switch off LED A (*)
0
15
reserved
Status reserved
..
..
..
6
..
..
5
reserved
Status reserved
4
Set SPI-Flash interface reset
Status SPI-Flash interface reset
3
Set USB internal access control bit 1
Status USB internal access control bit 1
2
Set USB internal access control bit 0
Status USB internal access control bit 0
1
Set Led test mode
Status Led test mode
0
Switch on LED A
Status User LED A
(1=LED on, 0=LED off)
(*) denotes power up default setting, i.e. the power up reading of the register is 0x0
USB internal access control bits:
