Watchdoggo

2017-05-16 10:01:08 +02:00
parent 601324b2a4
commit 191c10327f
6 changed files with 1110 additions and 961 deletions
--- a/PIC_Simulator/PIC/PICTimer.cs
+++ b/PIC_Simulator/PIC/PICTimer.cs
@@ -0,0 +1,87 @@
+
+namespace PIC_Simulator.PIC
+{
+	class PICTimer
+	{
+		private PICProgramm programm;
+
+		public PICTimer(PICProgramm p)
+		{
+			programm = p;
+		}
+
+		private bool prev_RA4 = false;
+		public void TimerBerechnen(uint cycles)
+		{
+			bool tmr_mode = programm.GetRegisterOhneBank(PICProgramm.ADDR_OPTION, PICProgramm.OPTION_BIT_T0CS);
+			bool edge_mode = programm.GetRegisterOhneBank(PICProgramm.ADDR_OPTION, PICProgramm.OPTION_BIT_T0SE);
+
+			if (!tmr_mode)
+			{
+				bool curr_A4 = programm.GetRegisterOhneBank(PICProgramm.ADDR_PORT_A, 4);
+
+				if (edge_mode)
+				{
+					if (prev_RA4 && !curr_A4)
+					{
+						TimerHochzaehlen(cycles);
+					}
+				}
+				else
+				{
+					if (!prev_RA4 && curr_A4)
+					{
+						TimerHochzaehlen(cycles);
+					}
+				}
+			}
+			else
+			{
+				TimerHochzaehlen(cycles);
+			}
+
+			prev_RA4 = programm.GetRegisterOhneBank(PICProgramm.ADDR_PORT_A, 4);
+		}
+
+		private uint prescale_cntr = 0; // Zähler für timer
+
+		private void TimerHochzaehlen(uint cycles)
+		{
+			uint current = programm.GetRegisterOhneBank(PICProgramm.ADDR_TMR0);
+			uint scale = BerechneVorskalierung();
+
+			prescale_cntr += cycles;
+
+			while (prescale_cntr >= scale)
+			{
+				prescale_cntr -= scale;
+
+				uint Result = current + 1;
+				if (Result > 0xFF)
+				{
+					//TODO Interrupt PIT_TIMER
+				}
+
+				Result %= 0x100;
+
+				uint tmp_psc = prescale_cntr;
+				programm.SetRegisterOhneBank(PICProgramm.ADDR_TMR0, Result);
+				prescale_cntr = tmp_psc;
+			}
+		}
+
+		private uint BerechneVorskalierung()
+		{
+			bool prescale_mode = programm.GetRegisterOhneBank(PICProgramm.ADDR_OPTION, PICProgramm.OPTION_BIT_PSA);
+
+			uint scale = 0;
+			scale += programm.GetRegisterOhneBank(PICProgramm.ADDR_OPTION, PICProgramm.OPTION_BIT_PS2) ? 1U : 0U;
+			scale *= 2;
+			scale += programm.GetRegisterOhneBank(PICProgramm.ADDR_OPTION, PICProgramm.OPTION_BIT_PS1) ? 1U : 0U;
+			scale *= 2;
+			scale += programm.GetRegisterOhneBank(PICProgramm.ADDR_OPTION, PICProgramm.OPTION_BIT_PS0) ? 1U : 0U;
+
+			return prescale_mode ? 1 : (PICProgramm.SHL(2, scale));
+		}
+	}
+}