American Dynamics PMC-4U-CACI User Manual
Page 18
Hardware and Software Design • Manufacturing Services
P a g e 18
Parallel termination resistors are supplied on each differential pair along
with a switch to allow the user to select which lines are terminated and
where. In some systems it will make sense to terminate the lines in the
cable and in others it will make sense to use the onboard terminations.
CONTROL
CORRESPONDING IO BITS
TERM0
IO_0..7
TERM1
IO_8..11
TERM2
IO_12..13
TERM3
IO_14..15
PMC4U_SW_IN
[0X14] PMC-4U User Switch Port read only
USER CONTROL SWITCH REGISTER
DATA BIT
DESCRIPTION
5
UB5
4
UB4
3
UB3
2
UB2
1
UB1
0
UB0
FIGURE 8
PMC-4U SWITCH READ BIT MAP
The Switch Read Port has the user bits. The user bits are connected to 6
switch positions. The switches allow custom configurations to be defined
by the user and for the software to “know” how to configure the read/write
capabilities of each IO line. Please note that the lower 6 bits of the switch
are implemented [positions 7 & 8 are unused]. The silk-screen is marked
with the ‘0’ and ‘1’ definitions.