def main():
dt = 0.01e-6
cap = 0.16e-6
ind = 0.16e-6
res = 0.1
model = MixedSignalModel('model', dt=dt)
model.add_analog_input('v_in')
model.add_analog_output('v_out')
model.add_analog_state('i_ind', 100)
v_l = AnalogSignal('v_l')
v_r = AnalogSignal('v_r')
eqns = [
Deriv(model.i_ind) == v_l / ind,
Deriv(model.v_out) == model.i_ind / cap, v_r == model.i_ind * res,
model.v_in == model.v_out + v_l + v_r
]
model.add_eqn_sys(eqns)
model.compile_and_print(VerilogGenerator())
def main(cap=0.16e-6, ind=0.16e-6, res=0.1):
print('Running model generator...')
# parse command line arguments
parser = ArgumentParser()
parser.add_argument('-o', '--output', type=str)
parser.add_argument('--dt', type=float)
args = parser.parse_args()
# create the model
model = MixedSignalModel('rlc',
AnalogInput('v_in'),
AnalogOutput('v_out'),
dt=args.dt)
model.add_analog_state('i_ind', 100)
# internal variables
v_l = AnalogSignal('v_l')
v_r = AnalogSignal('v_r')
# define dynamics
eqns = [
Deriv(model.i_ind) == v_l / ind,
Deriv(model.v_out) == model.i_ind / cap, v_r == model.i_ind * res,
model.v_in == model.v_out + v_l + v_r
]
model.add_eqn_sys(eqns)
# define probes
#model.add_probe(model.i_ind)
# determine the output filename
filename = os.path.join(get_full_path(args.output),
f'{model.module_name}.sv')
print('Model will be written to: ' + filename)
# generate the model
model.compile_to_file(VerilogGenerator(), filename)
def test_check_format(in_type, in_opt, out_type, out_opt, check_format, cycle,
expected_result, init_val):
# declare model I/O
m = MixedSignalModel('model')
if in_type == 'uint':
m.add_digital_input('a', width=in_opt)
elif in_type == 'sint':
m.add_digital_input('a', width=in_opt, signed=True)
elif in_type == 'real':
m.add_analog_input('a')
else:
raise Exception(f'Invalid in_type: {in_type}')
if out_type == 'uint':
m.add_digital_state('y', width=out_opt, init=init_val)
elif out_type == 'sint':
m.add_digital_state('y', width=out_opt, signed=True, init=init_val)
elif out_type == 'real':
m.add_analog_state('y', range_=out_opt)
else:
raise Exception(f'Invalid out_type: {out_type}')
if cycle == 'this':
m.set_this_cycle(m.y, m.a, check_format=check_format)
elif cycle == 'next':
m.set_next_cycle(m.y, m.a, check_format=check_format)
else:
raise Exception(f'Invalid cycle type: {cycle}')
# compile to a file
if expected_result is not None:
with pytest.raises(Exception) as e:
m.compile(VerilogGenerator())
assert expected_result in str(e.value)
else:
m.compile(VerilogGenerator())
def __init__(self, filename=None, **system_values):
# set a fixed random seed for repeatability
np.random.seed(0)
module_name = Path(filename).stem
build_dir = Path(filename).parent
#This is a wonky way of validating this.. :(
assert (all([req_val in system_values for req_val in self.required_values()])), \
f'Cannot build {module_name}, Missing parameter in config file'
m = MixedSignalModel(module_name, dt=system_values['dt'], build_dir=build_dir,
real_type=get_dragonphy_real_type())
# Random number generator seeds (defaults generated with random.org)
m.add_digital_input('jitter_seed', width=32)
m.add_digital_input('noise_seed', width=32)
# Chunk of bits from the history; corresponding delay is bit_idx/freq_tx delay
m.add_digital_input('chunk', width=system_values['chunk_width'])
m.add_digital_input('chunk_idx', width=int(ceil(log2(system_values['num_chunks']))))
# Control code for the corresponding PI slice
m.add_digital_input('pi_ctl', width=system_values['pi_ctl_width'])
# Indicates sequencing of ADC slice within a bank (typically a static value)
m.add_digital_input('slice_offset', width=int(ceil(log2(system_values['slices_per_bank']))))
# Control codes that affect states in the slice
m.add_digital_input('sample_ctl')
m.add_digital_input('incr_sum')
m.add_digital_input('write_output')
# ADC sign and magnitude
m.add_digital_output('out_sgn')
m.add_digital_output('out_mag', width=system_values['n_adc'])
# Emulator clock and reset
m.add_digital_input('clk')
m.add_digital_input('rst')
# Noise controls
m.add_analog_input('jitter_rms')
m.add_analog_input('noise_rms')
# Create "placeholder function" that can be updated
# at runtime with the channel function
chan_func = PlaceholderFunction(
domain=system_values['func_domain'],
order=system_values['func_order'],
numel=system_values['func_numel'],
coeff_widths=system_values['func_widths'],
coeff_exps=system_values['func_exps']
)
# Check the function on a representative test case
chan = Filter.from_file(get_file('build/chip_src/adapt_fir/chan.npy'))
self.check_func_error(chan_func, chan.interp)
# Add digital inputs that will be used to reconfigure the function at runtime
wdata, waddr, we = add_placeholder_inputs(m=m, f=chan_func)
# Sample the pi_ctl code
m.add_digital_state('pi_ctl_sample', width=system_values['pi_ctl_width'])
m.set_next_cycle(m.pi_ctl_sample, m.pi_ctl, clk=m.clk, rst=m.rst, ce=m.sample_ctl)
# compute weights to apply to pulse responses
weights = []
for k in range(system_values['chunk_width']):
# create a weight value for this bit
weights.append(
m.add_analog_state(
f'weights_{k}',
range_=system_values['vref_tx']
)
)
# select a single bit from the chunk. chunk_width=1 is unfortunately
# a special case because some simulators don't support the bit-selection
# syntax on a single-bit variable
chunk_bit = m.chunk[k] if system_values['chunk_width'] > 1 else m.chunk
# write the weight value
m.set_next_cycle(
weights[-1],
if_(
chunk_bit,
system_values['vref_tx'],
-system_values['vref_tx']
),
clk=m.clk,
rst=m.rst
)
# Compute the delay due to the PI control code
delay_amt_pre = m.bind_name(
'delay_amt_pre',
m.pi_ctl_sample / ((2.0**system_values['pi_ctl_width'])*system_values['freq_rx'])
)
# Add jitter to the sampling time
if system_values['use_jitter']:
# create a signal to represent jitter
delay_amt_jitter = m.set_gaussian_noise(
'delay_amt_jitter',
std=m.jitter_rms,
lfsr_init=m.jitter_seed,
clk=m.clk,
ce=m.sample_ctl,
rst=m.rst
)
# add jitter to the delay amount (which might possibly yield a negative value)
delay_amt_noisy = m.bind_name('delay_amt_noisy', delay_amt_pre + delay_amt_jitter)
# make the delay amount non-negative
delay_amt = m.bind_name('delay_amt', if_(delay_amt_noisy >= 0.0, delay_amt_noisy, 0.0))
else:
delay_amt = delay_amt_pre
# Compute the delay due to the slice offset
t_slice_offset = m.bind_name('t_slice_offset', m.slice_offset/system_values['freq_rx'])
# Add the delay amount to the slice offset
t_samp_new = m.bind_name('t_samp_new', t_slice_offset + delay_amt)
# Determine if the new sampling time happens after the end of this period
t_one_period = m.bind_name('t_one_period', system_values['slices_per_bank']/system_values['freq_rx'])
exceeds_period = m.bind_name('exceeds_period', t_samp_new >= t_one_period)
# Save the previous sample time
t_samp_prev = m.add_analog_state('t_samp_prev', range_=system_values['slices_per_bank']/system_values['freq_rx'])
m.set_next_cycle(t_samp_prev, t_samp_new-t_one_period, clk=m.clk, rst=m.rst, ce=m.sample_ctl)
# Save whether the previous sample time exceeded one period
prev_exceeded = m.add_digital_state('prev_exceeded')
m.set_next_cycle(prev_exceeded, exceeds_period, clk=m.clk, rst=m.rst, ce=m.sample_ctl)
# Compute the sample time to use for this period
t_samp_idx = m.bind_name('t_samp_idx', concatenate([exceeds_period, prev_exceeded]))
t_samp = m.bind_name(
't_samp',
array(
[
t_samp_new, # 0b00: exceeds_period=0, prev_exceeded=0
t_samp_new, # 0b01: exceeds_period=0, prev_exceeded=1
0.0, # 0b10: exceeds_period=1, prev_exceeded=0
t_samp_prev # 0b11: exceeds_period=1, prev_exceeded=1
], t_samp_idx
)
)
# Evaluate the step response function. Note that the number of evaluation times is the
# number of chunks plus one.
f_eval = []
for k in range(system_values['chunk_width']+1):
# compute change time as an integer multiple of the TX period
chg_idx = m.bind_name(
f'chg_idx_{k}', (
system_values['slices_per_bank']*system_values['num_banks']
- (m.chunk_idx+1)*system_values['chunk_width']
+ k
)
)
# scale by TX period
t_chg = m.bind_name(f't_chg_{k}', chg_idx/system_values['freq_tx'])
# compute the kth evaluation time
t_eval = m.bind_name(f't_eval_{k}', t_samp - t_chg)
# evaluate the function (the last three inputs are used for updating the function contents)
f_eval.append(m.set_from_sync_func(f'f_eval_{k}', chan_func, t_eval, clk=m.clk, rst=m.rst,
wdata=wdata, waddr=waddr, we=we))
# Compute the pulse responses for each bit
pulse_resp = []
for k in range(system_values['chunk_width']):
pulse_resp.append(
m.bind_name(
f'pulse_resp_{k}',
weights[k]*(f_eval[k] - f_eval[k+1])
)
)
# sum up all of the pulse responses
pulse_resp_sum = m.bind_name('pulse_resp_sum', sum_op(pulse_resp))
# update the overall sample value
sample_value_pre = m.add_analog_state('analog_sample_pre', range_=5*system_values['vref_rx'])
m.set_next_cycle(
sample_value_pre,
if_(m.incr_sum, sample_value_pre + pulse_resp_sum, pulse_resp_sum),
clk=m.clk,
rst=m.rst
)
# add noise to the sample value
if system_values['use_noise']:
sample_noise = m.set_gaussian_noise(
'sample_noise',
std=m.noise_rms,
clk=m.clk,
rst=m.rst,
ce=m.write_output,
lfsr_init=m.noise_seed
)
sample_value = m.bind_name('sample_value', sample_value_pre + sample_noise)
else:
sample_value = sample_value_pre
# there is a special case in which the output should not be updated:
# when the previous cycle did not exceed the period, but this one did
# in that case the sample value should be held constant
should_write_output = m.bind_name('should_write_output',
(prev_exceeded | (~exceeds_period)) & m.write_output)
# determine out_sgn (note that the definition is opposite of the typical
# meaning; "0" means negative)
out_sgn = if_(sample_value < 0, 0, 1)
m.set_next_cycle(m.out_sgn, out_sgn, clk=m.clk, rst=m.rst, ce=should_write_output)
# determine out_mag
vref_rx, n_adc = system_values['vref_rx'], system_values['n_adc']
abs_val = m.bind_name('abs_val', if_(sample_value < 0, -1.0*sample_value, sample_value))
code_real_unclamped = m.bind_name('code_real_unclamped', (abs_val / vref_rx) * ((2**(n_adc-1))-1))
code_real = m.bind_name('code_real', clamp_op(code_real_unclamped, 0, (2**(n_adc-1))-1))
# TODO: clean this up -- since real ranges are not intervals, we need to tell MSDSL
# that the range of the signed integer is smaller
code_sint = to_sint(code_real, width=n_adc+1)
code_sint.format_ = SIntFormat(width=n_adc+1, min_val=0, max_val=(2**(n_adc-1))-1)
code_sint = m.bind_name('code_sint', code_sint)
code_uint = m.bind_name('code_uint', to_uint(code_sint, width=n_adc))
m.set_next_cycle(m.out_mag, code_uint, clk=m.clk, rst=m.rst, ce=should_write_output)
# generate the model
m.compile_to_file(VerilogGenerator())
self.generated_files = [filename]