From 60b09a4b56d8d95cbd65945bdc2916145bc215e2 Mon Sep 17 00:00:00 2001
From: Richard Cornwell <rcornwell@github.com>
Date: Thu, 17 Sep 2020 20:12:21 -0400
Subject: [PATCH] IBM360: Fixed sense data in MT, minor 2703 fixes.

---
 IBM360/ibm360_com.c | 16 +++++++++++++---
 IBM360/ibm360_mt.c  | 12 +++++++-----
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/IBM360/ibm360_com.c b/IBM360/ibm360_com.c
index ed0220e..24a269d 100644
--- a/IBM360/ibm360_com.c
+++ b/IBM360/ibm360_com.c
@@ -272,7 +272,7 @@ uint8  coml_startcmd(UNIT *uptr, uint16 chan,  uint8 cmd) {
 
     switch (cmd & 0x3) {
     case 0x3:              /* Control */
-         if ((cmd == CMD_NOP) || (cmd & 0x8) != 0)
+         if ((cmd == CMD_NOP) || (cmd & 0x10) != 0)
              return SNS_CHNEND|SNS_DEVEND;
     case 0x2:              /* Read command */
     case 0x1:              /* Write command */
@@ -378,7 +378,7 @@ t_stat coml_srv(UNIT * uptr)
                  chan_end(addr, SNS_CHNEND|SNS_DEVEND|SNS_UNITEXP);
                  return SCPE_OK;
              }
-             if (uptr->CMD & ADDR) {
+             if ((uptr->CMD & ADDR) != 0 && uptr->BPTR == 0) {
                  ch = 0x16;
                  sim_debug(DEBUG_CMD, dptr, "COM: unit=%d addr %02x\n", unit, ch);
                  uptr->CMD &= ~ADDR;
@@ -408,6 +408,8 @@ t_stat coml_srv(UNIT * uptr)
                      chan_end(addr, SNS_CHNEND|SNS_DEVEND);
                      return SCPE_OK;
                  }
+//                 if (ch == 0x1f)
+//                     uptr->CMD |= ADDR;
                  ch = com_buf[unit][uptr->IPTR++];
                  if (chan_write_byte( addr, &ch)) {
                      uptr->CMD &= ~(0xff|INPUT|RECV);
@@ -436,6 +438,13 @@ t_stat coml_srv(UNIT * uptr)
                  chan_end(addr, SNS_CHNEND|SNS_DEVEND|SNS_UNITEXP);
                  return SCPE_OK;
              }
+             if (uptr->CMD & BREAK) {
+                 sim_debug(DEBUG_CMD, dptr, "COM: unit=%d attn write\n", unit);
+                 uptr->CMD &= ~(0xff|BREAK);
+                 uptr->SNS |= SNS_INTVENT;
+                 chan_end(addr, SNS_CHNEND|SNS_DEVEND|SNS_UNITCHK);
+                 return SCPE_OK;
+             }
              sim_debug(DEBUG_CMD, dptr, "COM: unit=%d write\n", unit);
              if (chan_read_byte (addr, &ch)) {
                  uptr->CMD &= ~0xff;
@@ -471,6 +480,7 @@ t_stat coml_srv(UNIT * uptr)
 
     case CMD_BRK:        /* Send break signal  */
          uptr->CMD &= ~0xff;
+         uptr->CMD |= ADDR;
          uptr->SNS = 0;
          chan_end(addr, SNS_CHNEND|SNS_DEVEND);
          break;
@@ -694,7 +704,7 @@ return SCPE_OK;
 
 const char *com_description (DEVICE *dptr)
 {
-return "IBM 2701 communications controller";
+return "IBM 2703 communications controller";
 }
 
 #endif
diff --git a/IBM360/ibm360_mt.c b/IBM360/ibm360_mt.c
index fe3c590..e712636 100644
--- a/IBM360/ibm360_mt.c
+++ b/IBM360/ibm360_mt.c
@@ -254,7 +254,6 @@ uint8  mt_startcmd(UNIT *uptr, uint16 chan,  uint8 cmd) {
     case 0x2:              /* Read command */
     case 0xc:              /* Read backward */
          uptr->SNS = 0;
-         uptr->SNS |= SNS_TUASTA << 8;
           /* Fall through */
 
     case 0x4:              /* Sense */
@@ -402,10 +401,13 @@ t_stat mt_srv(UNIT * uptr)
          ch = (uptr->SNS >> 8) & 0xff;
          if ((uptr->flags & MTUF_9TR) == 0)
              ch |= SNS_7TRACK;
-         if (sim_tape_wrp(uptr))
-             ch |= SNS_WRP;
-         if (sim_tape_bot(uptr))
-             ch |= SNS_LOAD;
+         if ((uptr->flags & UNIT_ATT) != 0) {
+             if (sim_tape_wrp(uptr))
+                 ch |= SNS_WRP;
+             if (sim_tape_bot(uptr))
+                 ch |= SNS_LOAD;
+             ch |= SNS_TUASTA;
+         }
          sim_debug(DEBUG_DETAIL, dptr, "sense unit=%d 2 %x\n", unit, ch);
          chan_write_byte(addr, &ch) ;
          ch = 0xc0;