问题
I have a GP-IB card in my PC connected to a DMM via GP-IB. I have ran diagnostician on the card and confirms it is working. I am able to control it threw there software test. Now I am trying to create a program to do it, but when it sends the command it always gives error on DMM.
I have 3 source files Master.pas, SubClass.pas, and ApiGpib.pas
In master.pas I have this to send a command to the device.
var
Ret : DWORD;
Yradr : DWORD;
Srlen : DWORD;
Cmd : array[0..31] of DWORD;
csBuf : String;
/Sending a command to the device////////////////////////////////////////////////
procedure TFormMaster1.ButtonSENDClick(Sender: TObject);
var
srBuffer: String; // command
SendBuf: PChar;
begin
Yradr := StrToInt(YRADRBox.Text); //card address
srBuffer := EditSENDDATA.Text;
Srlen := Length(srBuffer); // Length of text
SendBuf := PChar(srBuffer); // change string to Pchar
if Srlen <> $0 then //string no empty
begin // Send a command
EditTEXTRET.Text := 'Waiting for return???';
Refresh();
Cmd[0] := 2; // Number of equipment to talk to
Cmd[1] := Myadr; // My device address
Cmd[2] := Yradr; // Card address
Ret := GpTalk(@Cmd, Srlen, SendBuf); // Sends address's, length, text
CheckRet('GpTalk', (Ret and $FF), csBuf); // return value up to 255 length
EditTEXTRET.Text := csBuf; // Return text
end
else
EditTEXTRET.Text := 'No text to send';
end;
Now in ApiGpib.pas I have the functions GpTalk like so.
type
PDWORD=^DWORD
function GpTalk(Cmd:PDWORD; Srlen:DWORD; Srbuf:PChar):DWORD;stdcall;
...
...
...
Implementation
function GpTalk; external 'ApiGpib1.dll' ;
It will error out here on DMM, I cant view the ApiGpib1.dll.
- Question is
+Do you see anything wrong with the logic?
+What can I try in troubleshooting as to why this dont work?
Last of all just incase its something in the CheckRet function. In Subclass.pas I have this.
type
function CheckRet(Func:String;Ret:DWORD;var csBuf:string):DWORD;
Implementation
function CheckRet(Func: String; Ret: DWORD; var csBuf: String):DWORD;
var
RetCode,Ret1: DWORD;
begin
RetCode := 0;
Ret1 := Ret and $ff;
if Ret1 >= 3 then
begin
RetCode := 1;
case Ret1 of
3: csBuf := Func + ' : FIFO“à‚É‚Ü‚¾ƒf[ƒ^‚ªŽc‚Á‚Ä‚¢‚Ü‚·B';
80: csBuf := Func + ' : I/OƒAƒhƒŒƒXƒGƒ‰[‚Å‚·B';
82: csBuf := Func + ' : ƒŒƒWƒXƒgƒŠÝ’è‚̃Gƒ‰[‚Å‚·BConfig.exe‚ÅŠm”F‚µ‚Ä‚‚¾‚³‚¢B';
128: csBuf := Func + ' : ŽóMƒoƒbƒtƒ@‚ð’´‚¦‚½A‚Ü‚½‚ÍSRQ‚ðŽóM‚µ‚Ä‚¢‚Ü‚¹‚ñB';
200: csBuf := Func + ' : ƒXƒŒƒbƒh‚ªì¬‚Å‚«‚Ü‚¹‚ñB';
201: csBuf := Func + ' : ‘¼‚̃Cƒxƒ“ƒgŠÖ”‚ªŽÀs’†‚Å‚·B';
210: csBuf := Func + ' : DMA‚ªÝ’è‚Å‚«‚Ü‚¹‚ñ‚Å‚µ‚½B';
240: csBuf := Func + ' : EscƒL[‚ª‰Ÿ‚³‚ê‚Ü‚µ‚½B';
241: csBuf := Func + ' : ƒtƒ@ƒCƒ‹“üo—̓Gƒ‰[‚Å‚·B';
242: csBuf := Func + ' : ƒAƒhƒŒƒXŽw’肪ŠÔˆá‚Á‚Ä‚¢‚Ü‚·B';
245: csBuf := Func + ' : ƒoƒbƒtƒ@‚ª¬‚³‚·‚¬‚Ü‚·';
246: csBuf := Func + ' : •s³‚ȃIƒuƒWƒFƒNƒg–¼‚Å‚·B';
247: csBuf := Func + ' : ƒfƒoƒCƒX–¼‚̉¡‚̃`ƒFƒbƒN‚ª–³Œø‚Å‚·B';
248: csBuf := Func + ' : •s³‚ȃf[ƒ^Œ^‚Å‚·B';
249: csBuf := Func + ' : ‚±‚êˆÈãƒfƒoƒCƒX‚ð’ljÁ‚Å‚«‚Ü‚¹‚ñB';
250: csBuf := Func + ' : ƒfƒoƒCƒX–¼‚ªŒ©‚‚©‚è‚Ü‚¹‚ñB';
251: csBuf := Func + ' : ƒfƒŠƒ~ƒ^‚ªƒfƒoƒCƒXŠÔ‚ňá‚Á‚Ä‚¢‚Ü‚·B';
252: csBuf := Func + ' : GP-IBƒGƒ‰[‚Å‚·B';
253: csBuf := Func + ' : ƒfƒŠƒ~ƒ^‚Ì‚Ý‚ðŽóM‚µ‚Ü‚µ‚½B';
254: csBuf := Func + ' : ƒ^ƒCƒ€ƒAƒEƒg‚µ‚Ü‚µ‚½B';
255: csBuf := Func + ' : ƒpƒ‰ƒ[ƒ^ƒGƒ‰[‚Å‚·B';
end;
end
else
csBuf := Func + ' : ³íI—¹‚µ‚Ü‚µ‚½B';
Ret1 := Ret and $ff00;
case Ret1 of
$100: csBuf := csBuf + ' -- [SRQ]‚ðŽóM<STATUS>'; // 10 -> [256]
$200: csBuf := csBuf + ' -- [IFC]‚ðŽóM<STATUS>'; // 10 -> [512]
$300: csBuf := csBuf + ' -- [SRQ]‚Æ[IFC]‚ðŽóM<STATUS>'; // 10 -> [768]
end;
Result := RetCode;
end;
EDIT Found the GpTalk function thats in the dll. Might help find an error?
Format
(C)
DWORD Srlen, Ret;
DWORD * Cmd;
char * Srbuf;
Ret = GpTalk(Cmd, Srlen, Srbuf);
(Visual Basic)
Dim Srlen As Long, Ret As Long
Dim Cmd(xxxx) As Long '(xxxx specifies the maximum number of command arrays.)
Dim Srbuf As String
Dim SrbufB(xxxx) As Byte '(xxxx specifies the maximum amount of data.)
Ret = GpTalk(Cmd(0), Srlen, Srbuf)
Ret = GpTalkBinary(Cmd(0), Srlen, SrbufB(0))
Mode Master mode/Slave mode
Parameters
Cmd :
[0] Number of talkers and listeners ( = Number of listeners+1)
(Slave mode = 0)
[1] Talker address
[2] Listener address
Srlen : Transmit data length (byte)
Srbuf : Transmit data
SrbufB : Transmit data array(for binary)
Ret : Return value
0 : Normal completion
80 : GpIni() hasn't execute
140 : Asynchronous function is executing now
240 : ESC key pressed
242 : Miss in address specified
243 : Miss in buffers
252 : GP-IB error
254 : Timeout
255 : Illegal call
Notes
1 Command array:
Since the number of commands to be sent is given to Cmd[0], specify 0 for Cmd[0] in slave mode.
2 1Mbyte will be sent if transmit data length = 0.
3 If you have already used DOS-Version, you do not need to execute Dmainuse function when using FIFO.
4 When transmits binary data by VB, use GpTalkBinary. And secure buffers by Byte type. Refer to VB's help "unicode".
回答1:
- In D10-Seattle you have to use
PAnsiCharandAnsiStringfor data buffers
(becausePCharisPWideCharin modern Delphi versions). - Does GpTalk return data is
Srbuf? If so, is buffer length enough for response?
.
srBuffer: AnsiString; // command
SendBuf: PAnsiChar;
...
SendBuf := PAnsiChar(srBuffer); // change string to Pchar
...
function GpTalk(Cmd:PDWORD; Srlen:DWORD; Srbuf: PAnsiChar):DWORD;stdcall;
来源：https://stackoverflow.com/questions/35077071/gb-ip-function-not-working-correctly