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# Debug a simple bootloader
from zerotrap.cpu import ZeroTrapCPU
from zerotrap.bus import SystemBus
from zerotrap.devices.bus.ram import RAMDevice

# init the devices
bus = SystemBus()
cpu = ZeroTrapCPU(bus=bus)
ram = RAMDevice(size=1024*1024)

# load the test code
ram.load_data(bootloader_code, 0x07C00)

# attach the components
bus.attach_device(ram, 0x00000, 0xFFFFF) # 0x00000 - 0xFFFFF physical address

def debug_callback(cpu_obj, cmd):  # define a test callback
    # Get the registers
    registers = cpu_obj.registers
    # print
    print(f'[TRACE]. registers={registers}, cmd={cmd}')

# Optional: stdout -> file
import sys
sys.stdout = open('test.log', 'w')

# set the CPU state
cpu.set_reg('CS', 0x0000)
cpu.set_reg('IP', 0x7C00)

# run the test
cpu.run(callback=debug_callback, max_steps=-1) # -1 (or None) means no limit

# cpu runs until HLT or errors occurred.
print('test passed.')