36 TA2922 Universal Line Interface Service Manual
© Tait Electronics Limited  March 2010
SK1 I/O matrix SMD resistor placement
The top side of the I/O matrix is a 26 row x 9 column matrix of 0603 sized resistor 
pads which are used to factory define the input and output signals of each of the 
nine pins on the external D-range connector SK1.
Each pad is connected in parallel with a pair of solder link pads on the bottom side 
of the board, used for technicians to manually customise the function of each 
connector pin. See “SK1 I/O matrix bottom-side solder links” on page 37.
Important All variants of the TA2922 option board have all or some SK1 lines 
configured using zero ohm resistors on the top side of the I/O 
matrix. Before fitting solder links to the bottom side of the matrix, 
it is essential to remove existing components from the top side of 
the matrix or check carefully that existing links do not conflict 
with newly populated solder links on the bottom side. Failure to 
do so may result in unexpected operation or permanent damage 
to the TA2922 interface.
The table below indicates the relationship between each solder link pad and its 
associated SMD resistor location. Columns 1-9 are the external D-range connector 
pins while rows A-Z are the selectable I/O signals. See “SK1 I/O signal summary” 
on page 26.
SK1 external D-Range connector
I/O 
Signals
123456789
A
R1-2 R2-2 R3-2 R4-2 R5-2 R6-2 R7-2 R8-2 R9-2
B
R10-2 R11-2 R12-2 R13-2 R14-2 R15-2 R16-2 R17-2 R18-2
C
R19-2 R20-2 R21-2 R22-2 R23-2 R24-2 R25-2 R26-2 R27-2
D
R28-2 R29-2 R30-2 R31-2 R32-2 R33-2 R34-2 R35-2 R36-2
E
R37-2 R38-2 R39-2 R40-2 R41-2 R42-2 R43-2 R44-2 R45-2
F
R46-2 R47-2 R48-2 R49-2 R50-2 R51-2 R52-2 R53-2 R54-2
G
R55-2 R56-2 R57-2 R58-2 R59-2 R60-2 R61-2 R62-2 R63-2
H
R64-2 R65-2 R66-2 R67-2 R68-2 R69-2 R70-2 R71-2 R72-2
I
R73-2 R74-2 R75-2 R76-2 R77-2 R78-2 R79-2 R80-2 R81-2
J
R82-2 R83-2 R84-2 R85-2 R86-2 R87-2 R88-2 R89-2 R90-2
K
R91-2 R92-2 R93-2 R94-2 R95-2 R96-2 R97-2 R98-2 R99-2
L
R100-2 R101-2 R102-2 R103-2 R104-2 R105-2 R106-2 R107-2 R108-2
M
R109-2 R110-2 R111-2 R112-2 R113-2 R114-2 R115-2 R116-2 R117-2
N
R118-2 R119-2 R120-2 R121-2 R122-2 R123-2 R124-2 R125-2 R126-2