Programming instructions

Intermec Fingerprint v7.61 – Programmer’s Reference Manual Ed. 750

Chapter 2 Program Instructions

COMSTAT

Field of Application

Function reading the status of the buffer of a communication channel.

Syntax COMSTAT(<nexp>)

<nexp> is one of the following communication channels:

1 = "uart1:"

2 = "uart2:"

3 = "uart3:"

4 = "centronics:"

5 = "net1:"

6 = "usb1:"

Remarks

This function is closely related to COMSET, ON COMSET GOSUB,

COMSET ON, COMSET OFF, COM ERROR ON/OFF, and COMBUF$.

It allows you to ﬁ nd out if the buffer is able to receive background data, or-

if not-what condition has caused the interruption.

The buffer’s status is indicated by a numeric expression, which is the sum

of the values given by the following conditions:

• Copy of hardware handshake bit (not on "net1:" or "usb1:") .........0 or 1

• Interruption: Max. number of characters received...................................2

• Interruption: End character received.........................................................4

• Interruption: Attention string received......................................................8

• Interruption: Communication error (not on "net1:" or "usb1:")........... 32

Example

A message will appear on the screen when the reception is interrupted by

any of four COMSET conditions being fulﬁ lled:

10 COM ERROR 1 ON

20 A$="Max. number of char. received"

30 B$="End char. received"

40 C$="Attn. string received"

50 D$="Communication error"

60 COMSET 1, "A",CHR$(90),"#","BREAK",20

70 ON COMSET 1 GOSUB 1000

80 COMSET 1 ON

90 IF QDATA$="" THEN GOTO 90

100 END

1000 QDATA$=COMBUF$(1)

1010 IF COMSTAT(1) AND 2 THEN PRINT A$

1020 IF COMSTAT(1) AND 4 THEN PRINT B$

1030 IF COMSTAT(1) AND 8 THEN PRINT C$

1040 IF COMSTAT(1) AND 32 THEN PRINT D$

1050 PRINT QDATA$

1060 RETURN