Reference Manual

Turbo PMAC/PMAC2 Software Reference

Turbo PMAC Global I-Variables 67

I63 Control-X Echo Enable

Range: 0 – 1

Units: None

Default: 1

I63 permits the PMAC to echo the <CONTROL-X> character back to the host computer when it is

received. If I63 is set to 1, PMAC will send a <CONTROL-X> character (ASCII value 24 decimal) back

to the host computer when it receives a <CONTROL-X> character.

If I63 is set to 0, PMAC will send nothing back to the host computer when it receives a <CONTROL-X>

character. This is equivalent to the action of older versions of PMAC firmware without an I63 variable.

The host computer can use the <CONTROL-X> character to clear out PMAC’s communications buffers

and make sure that no unintended responses are received for the next command. However, without an

acknowledgement that the buffers have been cleared, the host computer has to add a safe delay to ensure

that the operation has been done before the next command can be issued.

Setting I63 to 1 permits a more efficient clearing of the buffer, because the response character lets the

host computer know when the next command can safely be sent.

Versions of the Pcomm 32 communications library 2.21 and higher (March 1999 and newer) can take

advantage of this feature for more efficient communications. I63 should be set to 0 when using older

versions of Pcomm 32.

I64 Internal Response Tag Enable

Range: 0 – 1

Units: None

Default: 0

I64 permits PMAC to tag ASCII text lines that it sends to the host computer as a result of internal

commands, so these can easily be distinguished from responses to host commands.

If I64 is set to 1, a line of text sent to the host computer as a result of an internal SEND or CMD statement

is preceded by a <CONTROL-B> (start-transmission) character. In the case of an error report, the

<CONTROL-B> character replaces the leading <CONTROL-G> (“bell”) character. The text line is always

terminated by a <CR> (carriage return) character, regardless of the setting of I62.

If I64 is set to 0, a text line sent in response to an internal PMAC command is not preceded by any special

character. Reported errors are preceded by the <CONTROL-G> (bell) character. This is equivalent to the

action of older versions of PMAC firmware, before I64 was implemented.

Regardless of the setting of I64, if I6 = 2, errors on internal commands are not reported to the host

computer.

Example:

With I64=0, lines sent from PMAC are:

Motion Stopped on Limit<CR>

With I64=1, the same lines from PMAC are:

<CTRL-B>Motion Stopped on Limit<CR>

<CTRL-B>ERR003<CR>

I65 User Configuration Variable

Range: 0 – 16,777,215

Units: none

Default: 0