Changeset 212bc4c in buchla-emu for emu

Timestamp:

08/02/2017 09:59:46 PM (7 years ago)

Author:

Alexander Heinrich <alex.heinrich@…>

Branches:

master

Children:

52c8401

Parents:

8967dbc

Message:

Add rudimentary timer

Add rudimentary timer that responds to the bios read and write requests
and sends an interrupt, if it has counted to 0.

Location:

emu

Files:

• cpu.c (modified) (1 diff)
• tim.c (modified) (4 diffs)

emu/cpu.c

@@ -70 +70 @@
         { 0x180000, 0x200000, 0, fpu_init, fpu_quit, fpu_exec, fpu_read, fpu_write },
         { 0x200000, 0x280000, 0, vid_init, vid_quit, vid_exec, vid_read, vid_write },
-        { 0x3a0001, 0x3a4001, 0, tim_init, tim_quit, tim_exec, tim_read, tim_write },
+        { 0x3a0001, 0x3a4001, 4, tim_init, tim_quit, tim_exec, tim_read, tim_write },
         { 0x3a4001, 0x3a8001, 0, lcd_init, lcd_quit, lcd_exec, lcd_read, lcd_write },
         { 0x3a8001, 0x3ac001, 5, ser_init, ser_quit, ser_exec, ser_read, ser_write },

emu/tim.c

@@ -22 +22 @@
 #define ver3(...) _ver(tim_verbose, 2, __VA_ARGS__)
 
+typedef struct {
+        uint32_t irq;
+        bool run;
+        uint32_t latch;
+        uint32_t count;
+} state_timer;
+
+static state_timer timers[] = {
+                {.irq = 0, .run = false, .latch = 32, .count = 32},
+                {.irq = 0, .run = false, .latch = 3200, .count = 3200},
+                {.irq = 0, .run = false, .latch = 801, .count = 801}
+};
+
+#define REG_CRX 0
+#define REG_CR2 1
+#define REG_T1H 2
+#define REG_T1L 3
+#define REG_T2H 4
+#define REG_T2L 5
+#define REG_T3H 6
+#define REG_T3L 7
+
 int32_t tim_verbose = 0;
 
@@ -36 +58 @@
 bool tim_exec(void)
 {
-        ver3("tim exec");
-        return false;
+        for (int32_t i = 0; i < ARRAY_COUNT(timers); ++i) {
+                if(timers[i].run == true) {
+                        --timers[i].count;
+                        if(timers[i].count == 0) {
+                                timers[i].count = timers[i].latch;
+                                timers[i].irq = 1;
+                        }
+                        //ver2("tim%d %u", i, timers[i].count);
+                }
+        }
+        return timers[0].irq || timers[1].irq || timers[2].irq;
 }
 
@@ -43 +74 @@
 {
         ver2("tim rd %u:%d", off, sz * 8);
-        return 0;
+        uint32_t rv;
+        rv = 0;
+        switch(off) {
+        case REG_CRX:
+                break;
+        case REG_CR2:
+                rv |= (timers[0].irq << 0);
+                rv |= (timers[1].irq << 1);
+                rv |= (timers[2].irq << 2);
+                ver2("tim plc %u fc %u rtc %u", timers[0].irq, timers[1].irq, timers[2].irq);
+                //ver2("tim rv %u", rv);
+                break;
+        case REG_T1H:
+                rv = 0;
+                break;
+        case REG_T1L:
+                rv = 31;
+                timers[0].irq = 0;
+                break;
+        case REG_T2H:
+                rv = 12;
+                break;
+        case REG_T2L:
+                rv = 127;
+                timers[1].irq = 0;
+                break;
+        case REG_T3H:
+                rv = 3;
+                break;
+        case REG_T3L:
+                rv = 32;
+                timers[2].irq = 0;
+                break;
+        default:
+                break;
+        }
+        return rv;
 }
 
@@ -49 +116 @@
 {
         ver2("tim wr %u:%d 0x%0*x", off, sz * 8, sz * 2, val);
+        if( off == 0 && (val & (1 << 7)) ) {
+                timers[0].run = true;
+                timers[1].run = true;
+                timers[2].run = true;
+        }
 }