Advantech PCLS-848-P, User Manual

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CHAPTER 2 INSTALLATION 71
(vecuo) relation is:
I R Q Vector No.(hex)
2 10 (0xA)
3 11 (0xB)
5 13 (0xD)
7 15 (0xF)
The steps to program interrupt handling for an IEEE-488 bus SRQ ft is as follows:
1) Call ieinit( ) procedure to set IRQ channel.
2) Set the vector and service routine.
3) After returning from the service routine, program the following statements to enable
the next SRQ interrupt.
1. Write port 20Hex with 20Hex to enable 8259 chip.
2. Read register 2 of NEC7210 to clear the SRQ bit. The port address is
default to 2BAHex.
5.4. More about the Procedure iesend( )
The iesend( ) procedure allows the user to control the IEEE-488 interface directly.
Therefore, some unusual functions of the IEEE-488 function can be done by calling
iesend( ).
An example is PASSING CONTROL to another device. This can be done by
executing the following statements. This example passes control to device 22.
cmdstr:lstring(80);
cmdstr:=’UNL UNT TALK 22 TCT’;
iesend(cmdstr);
Some instruments use secondary addressing technique. To write a data string to
secondary address 03 with primary address 23, the program is as follows: