From 9cef8d12c25eacf2d2d57c0685ed591f9bc916a8 Mon Sep 17 00:00:00 2001
From: Richard Cornwell <rcornwell@github.com>
Date: Sun, 24 Nov 2019 13:56:15 -0500
Subject: [PATCH] SCP: Updated display to current.

---
 display/type340.c | 46 +++++++++++++++++++++++++++++++++++++++++++---
 display/type340.h |  6 ++++++
 2 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/display/type340.c b/display/type340.c
index 2e65617..32fc8cf 100644
--- a/display/type340.c
+++ b/display/type340.c
@@ -115,9 +115,7 @@ enum jump_type { DJP=2, DJS=3, DDS=1 }; /* type 347 */
 
 /* put all the state in a struct "just in case" */
 static struct type340 {
-#ifdef NOTYET
     ty340word DAC;              /* Display Address Counter */
-#endif
     ty340word status;           /* see ST340_XXX in type340.h */
     signed short xpos, ypos;    /* 10 bits, signed (for OOB checks) */
     char initialized;           /* 0 before display_init */
@@ -143,7 +141,6 @@ static struct type340 {
 #define UNIT(N) (u340+(N))
 #endif
 
-#if 0
 /* NOT USED WITH PDP-6 Type 344 Interface!! */
 void
 ty340_set_dac(ty340word addr)
@@ -157,7 +154,50 @@ ty340_set_dac(ty340word addr)
     u->status = 0;               /* XXX just clear stopped? */
     ty340_rfd();                 /* ready for data */
 }
+
+void
+ty340_cycle(void)
+{
+    struct type340 *u = UNIT(0);
+
+    if (u->status == 0) {
+        ty340word insn = ty340_fetch(u->DAC);
+        u->status = ty340_instruction (insn);
+        u->DAC = (u->DAC + 1) & 07777;
+    }
+}
+
+ty340word
+ty340_get_dac(void)
+{
+    struct type340 *u = UNIT(0);
+    return u->DAC;
+}
+
+ty340word
+ty340_get_asr(void)
+{
+#if TYPE347
+    struct type340 *u = UNIT(0);
+    return u->ASR;
+#else
+    return 0;
 #endif
+}
+
+ty340word
+ty340_sense(ty340word flags)
+{
+    struct type340 *u = UNIT(0);
+    return u->status & flags;
+}
+
+void
+ty340_clear(ty340word flags)
+{
+    struct type340 *u = UNIT(0);
+    u->status &= ~flags;
+}
 
 ty340word
 ty340_reset(void *dptr)
diff --git a/display/type340.h b/display/type340.h
index 1c39dc1..5caf06d 100644
--- a/display/type340.h
+++ b/display/type340.h
@@ -49,7 +49,13 @@ typedef unsigned int ty340word;
 ty340word ty340_reset(void *);
 ty340word ty340_status(void);
 ty340word ty340_instruction(ty340word inst);
+ty340word ty340_get_dac(void);
+ty340word ty340_get_asr(void);
+ty340word ty340_sense(ty340word);
 void ty340_set_dac(ty340word addr);
+void ty340_clear(ty340word addr);
+void ty340_cycle(void);
+void ty340_set_status(ty340word);
 void ty342_set_grid(int, int);
 
 /*