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CHAPTER 5: Command Descriptions
CLEAR Command
The CLEAR command causes the Device Clear (DCL) bus command to be issued by the 488 Controller. If
the optional addresses are included, the Selected Device Clear (SDC) command is issued to all specified
devices. IEEE 488 bus devices which receive a Device Clear or Selected Device Clear command normally
reset to their power-on state.
SYNTAX
CLEAR [addr[,addr]]
or
CL [addr[,addr]]
addr
is a device address (primary with optional secondary).
,
is the address separator—either a comma, a slash [/], or a period [.].
RESPONSE
None
MODE
CA
BUS STATES
ATNDCL
(all devices)
ATNUNL,MTA,LAG,SDC
(selected devices)
EXAMPLES:
PRINT #1,"CLEAR"
Issue a Device Clear to all devices.
PRINT #1, "CL 12, 18"
Issue a Selected Device Clear to devices 12 and 18.
COUNT Command
The COUNT command returns the loop count, appended with the serial output terminator(s), of the last
invoked macro buffer. If macro 1 requests a COUNT then calls macro 0, any subsequent COUNT requests
made by macro 1 will return the macro 0 loop COUNT. The following macro 1’s buffer contents illustrates
this.
MACRO 1
Creates macro buffer #1.
COUNT
This will return macro #1’s loop count.
DOMACRO 0
This command executes macro #0.
COUNT
This will return macro #0’s loop count, since it was the last macro to be invoked.
ENDM01
Содержание 488 Controller
Страница 94: ...488 CONTROLLER 92 9 2 Board Layout Figure 9 1 The 488 Controller s motherboard...
Страница 95: ...93 CHAPTER 9 Theory of Operation Board Layout Figure 9 2 The interface converter s serial I O board...
Страница 102: ...488 CONTROLLER 100 How To Read the Chart Hexadecimal Decimal Equivalent Equivalent ASCII Character Address or Command...