Technologic Systems TS-SER4, Manual

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Table 4 documents the physical I/O address 
locations for COM ports COM1 thru COM12.  
Since a Xilinx programmable logic device (PLD) 
is used to decode the I/O locations, it is possible 
to have the COM ports decoded at any location. 
Call Technologic Systems for more details. 
There are four status registers associated with 
each TS-SER4 board.  These registers contain 
the status of all the jumpers and also the status 
of the interrupts for each COM port.  These four 
registers have different I/O locations depending 
upon the Base COM port selected.  This allows 
for multiple TS-SER4 boards to be installed.   
Table 3 documents where the base address for 
these control and status registers is located.  
There are a total of six different Base locations 
to allow a total of six TS-SER4 boards in a 
single system.  Using a custom configuration in 
the Xilinx PLD, it is possible to have more than 
three boards in a system.  
 
 
 
 
 
 
 

5.  Control and Status Registers 

There are four registers on each TS-SER4 board (unrelated to the UARTs).  These 
registers are documented in Table 5 below.  The first three registers are “Read Only” 
while in the fourth register bit 7 is “Read/Write” and bits 0-6 are “Read Only”.  For all 
registers, if a condition is true, a logic “1” is returned.  For example, when a jumper is 
present, a logic “1” is returned.  For the Base + 1 address, if an interrupt is pending, the 
respective status bit is set to a logic “1”. 
The Base address (Base + 0) always returns a fixed value of 7A (Hex). 
The Base + 1 address returns the status of the 4 interrupt sources from COM_A, 
COM_B, COM_C, and COM_D.  This is essential for sharing interrupts and allows the 
interrupt service routine to determine which COM port has an interrupt pending.  When 
any of these sources has an interrupt pending, the respective status bit is set. 
The Base + 2 address returns the status of the jumpers that determine the Base COM 
port location (jumpers J_com1 thru J_com4) and the Base IRQ selected (jumpers J_irq1 
thru J_irq8). 
 
 

COM 

Port 

I/O location  (Hex) 

COM1

3F8 

COM2

2F8 

COM3

3E8 

COM4

2E8 

COM5

3A8 

COM6

2A8 

COM7

3A0 

COM8

2A0 

COM9

398 

COM10

298 

COM11

390 

COM12

290 

COM13

378 

COM14

278 

COM15

368 

COM16

268 

COM17

328 

COM18

228 

COM19

320 

COM20

220 

COM21

318 

COM22

218 

COM23

310 

COM24

210 

        Table 4 – COM port I/O locations