From b1891eba268cb6acd0dd1eca0c80adbaecd73bff Mon Sep 17 00:00:00 2001
From: root <root@avtech.domain.avtechpulse.com>
Date: Fri, 31 Dec 1999 20:24:15 -0500
Subject: first attempt to disentangle VXI and GPIB STB reporting

---
 gpib.c | 66 ++++++++++++++++--------------------------------------------------
 1 file changed, 16 insertions(+), 50 deletions(-)

(limited to 'gpib.c')

diff --git a/gpib.c b/gpib.c
index 3945447..46b1e14 100644
--- a/gpib.c
+++ b/gpib.c
@@ -261,7 +261,9 @@ void TNT_4882_Status(int status_register,unsigned int byte,int operation)
 {
 	int set_srq;
 
-	MR_4882_status[STB] = TNT_In(R_spsr);		// Get STB
+	if (globals.HWDetect.gpib) {
+		MR_4882_status[STB] = TNT_In(R_spsr);		// Get STB
+	}
 
 	switch (operation) {
 	case SET:
@@ -417,9 +419,8 @@ void GPIB_initialize(void)
 	Requested_Count=0;
 
 	// test to detect TNT chip
-	if ((TNT_In(R_sts2) & 0xB0) == 0x90) {
-		globals.HWDetect.gpib = 1;
-	} else {
+	globals.HWDetect.gpib = 1;
+	if ((TNT_In(R_sts2) & 0xB0) != 0x90) {
 		globals.HWDetect.gpib = 0;
 		printf ("Error: TNT4882 chip not found\n");
 		return;
@@ -588,12 +589,20 @@ static unsigned long int TNT_DATA_COUNT()
 
 static void TNT_Out(int reg, unsigned int byte)
 {
+        if (!globals.HWDetect.gpib) {
+                return;
+        }
+
 	bus_writebyte ((uint8_t) (TNT_Port + reg), (uint8_t) byte);
 }
 
 
 static unsigned char TNT_In(int reg)
 {
+        if (!globals.HWDetect.gpib) {
+                return (unsigned char) 0;
+        }
+
 	return (unsigned char) bus_readbyte ((uint8_t) (TNT_Port + reg));
 }
 
@@ -645,7 +654,7 @@ int GPIB_check_for_device_clear_signal(void)
 }
 
 
-int GPIB_and_VXI_device_clear(void)
+void GPIB_and_VXI_device_clear(void)
 {
 	TNT_Out(R_auxmr,F_clrDEC);
 	GPIB_and_VXI_clear_MAV();
@@ -806,10 +815,6 @@ void GPIB_and_VXI_start_query_response(gpointer ignore_this, gchar *in_string)
 
 void GPIB_finish_query_response()
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	if (globals.Registers.pending_output_message == NULL) {
 		return;
 	}
@@ -945,10 +950,6 @@ void GPIB_check_remote_status (int *is_remote, int *is_lockout)
 
 void GPIB_go_to_local ()
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_Out(R_auxmr,0x05);			// issue TNT rtl command
 	return;
 }
@@ -956,10 +957,6 @@ void GPIB_go_to_local ()
 
 void GPIB_clear_events ()
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(ESR,0xff,CLEAR);	// Clear ESR register
 	TNT_4882_Status(STB,0x20,CLEAR);	// Clear ESB bit in STB
 	return;
@@ -986,11 +983,8 @@ unsigned int GPIB_get_ESE ()
 
 unsigned int GPIB_and_VXI_get_STB ()
 {
-	if (!globals.HWDetect.gpib) {
-		return 0;
-	}
-
-	return (TNT_In(R_spsr)&0xbf) | (((TNT_In(R_spsr)&0xbf) & MR_4882_status[SRE])?0x40:0);
+//	return (TNT_In(R_spsr)&0xbf) | (((TNT_In(R_spsr)&0xbf) & MR_4882_status[SRE])?0x40:0);
+	return (MR_4882_status[STB]&0xbf) | (((MR_4882_status[STB]&0xbf) & MR_4882_status[SRE])?0x40:0);
 }
 
 
@@ -1008,70 +1002,42 @@ void GPIB_and_VXI_clear_MAV()
 
 void GPIB_set_ESR (unsigned int byte,int operation)
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(ESR,byte,operation);
 }
 
 
 void GPIB_set_SRE (unsigned int byte,int operation)
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(SRE,byte,operation);
 }
 
 
 void GPIB_set_ESE (unsigned int byte,int operation)
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(ESE,byte,operation);
 }
 
 
 void GPIB_Set_Execution_Error ()
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(ESR,0x10,1);
 }
 
 
 void GPIB_Set_Command_Error ()
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(ESR,0x20,1);
 }
 
 
 void GPIB_Set_Query_Error ()
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(ESR,0x04,1);
 }
 
 
 void GPIB_Set_Device_Dependent_Error ()
 {
-	if (!globals.HWDetect.gpib) {
-		return;
-	}
-
 	TNT_4882_Status(ESR,0x08,1);
 }
 
-- 
cgit