EMualtor im

2026-05-25 18:43:36 +10:00
parent 81f5d7a150
commit 05e1237acc
18 changed files with 993 additions and 20 deletions
--- a/tests/test_emulator_timers.py
+++ b/tests/test_emulator_timers.py
@@ -0,0 +1,78 @@
+import unittest
+
+from h8536.emulator import H8536Emulator, ON_CHIP_RAM_START
+from h8536.emulator.constants import (
+    FRT_TCR_OCIEA,
+    FRT_TCSR_OCFA,
+    FRT2_TCR,
+    FRT2_TCSR,
+    IPRC,
+    VECTOR_FRT2_OCIA,
+)
+
+
+def rom_with_reset(*, reset: int = 0x1000, size: int = 0x1040) -> bytearray:
+    rom = bytearray([0xFF] * size)
+    rom[0:2] = reset.to_bytes(2, "big")
+    return rom
+
+
+def write_mov_b_abs_imm(rom: bytearray, address: int, target: int, value: int) -> int:
+    rom[address : address + 5] = bytes([0x15, (target >> 8) & 0xFF, target & 0xFF, 0x06, value & 0xFF])
+    return address + 5
+
+
+class Frt2OciaTimerTest(unittest.TestCase):
+    def test_frt2_ocia_vector_can_fire_and_decrement_ram(self):
+        rom = rom_with_reset()
+        rom[VECTOR_FRT2_OCIA : VECTOR_FRT2_OCIA + 2] = (0x1020).to_bytes(2, "big")
+
+        pc = 0x1000
+        rom[pc : pc + 3] = b"\x5F\xFE\x80"  # MOV:I.W #H'FE80, R7
+        pc += 3
+        # IPRC bits 6..4 are FRT1 and bits 2..0 are FRT2, so H'06 makes
+        # only the FRT2 priority field high enough to pass interrupt mask 0.
+        pc = write_mov_b_abs_imm(rom, pc, IPRC, 0x06)
+        pc = write_mov_b_abs_imm(rom, pc, FRT2_TCR, FRT_TCR_OCIEA)
+        rom[pc : pc + 2] = b"\x20\xFE"  # BRA self
+
+        isr = 0x1020
+        rom[isr : isr + 4] = bytes([0x15, (ON_CHIP_RAM_START >> 8) & 0xFF, ON_CHIP_RAM_START & 0xFF, 0x0C])
+        isr += 4
+        rom[isr : isr + 4] = bytes([0x15, (FRT2_TCSR >> 8) & 0xFF, FRT2_TCSR & 0xFF, 0xD5])
+        rom[isr + 4] = 0x0A  # RTE
+
+        emulator = H8536Emulator(bytes(rom), frt2_ocia_steps=2)
+        emulator.memory.write8(ON_CHIP_RAM_START, 3)
+        emulator.run(max_steps=5)
+
+        self.assertEqual(emulator.memory.read8(ON_CHIP_RAM_START), 2)
+        self.assertFalse(emulator.memory.read8(FRT2_TCSR) & FRT_TCSR_OCFA)
+        self.assertEqual(emulator.cpu.pc, isr + 4)
+
+    def test_frt2_ocia_does_not_fire_when_ociea_disabled(self):
+        rom = rom_with_reset()
+        rom[VECTOR_FRT2_OCIA : VECTOR_FRT2_OCIA + 2] = (0x1020).to_bytes(2, "big")
+
+        pc = 0x1000
+        rom[pc : pc + 3] = b"\x5F\xFE\x80"  # MOV:I.W #H'FE80, R7
+        pc += 3
+        pc = write_mov_b_abs_imm(rom, pc, IPRC, 0x06)
+        rom[pc : pc + 2] = b"\x20\xFE"  # BRA self
+
+        rom[0x1020 : 0x1024] = bytes(
+            [0x15, (ON_CHIP_RAM_START >> 8) & 0xFF, ON_CHIP_RAM_START & 0xFF, 0x0C]
+        )
+        rom[0x1024] = 0x0A  # RTE
+
+        emulator = H8536Emulator(bytes(rom), frt2_ocia_steps=1)
+        emulator.memory.write8(ON_CHIP_RAM_START, 3)
+        emulator.run(max_steps=8)
+
+        self.assertEqual(emulator.memory.read8(ON_CHIP_RAM_START), 3)
+        self.assertEqual(emulator.memory.read8(FRT2_TCSR) & FRT_TCSR_OCFA, 0)
+        self.assertEqual(emulator.cpu.pc, pc)
+
+
+if __name__ == "__main__":
+    unittest.main()