/
shared_uart.py
49 lines (34 loc) · 1.1 KB
/
shared_uart.py
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"""
UART which is connected to multiple sets of pins.
"""
import operator
from migen import *
from litex.soc.cores import uart
class UARTVirtualPhy(Module):
def __init__(self):
self.sink = Endpoint([("data", 8)])
self.source = Endpoint([("data", 8)])
class SharedUART(Module):
def __init__(self, clk_freq, baud_rate):
self.tx = Signal()
self.rx = Signal()
self.tx_signals = []
self.rx_signals = []
self.submodules.phy = uart.RS232PHY(self, clk_freq, baud_rate)
self.submodules.uart = uart.UART(self.phy)
def add_uart_pads(self, new_pads):
self.tx_signals.append(new_pads.tx)
self.rx_signals.append(new_pads.rx)
def do_finalize(self):
if self.tx_signals:
for tx_sig in self.tx_signals:
self.comb += [
# TX
tx_sig.eq(self.tx),
]
if self.rx_signals:
self.comb += [
# RX
self.rx.eq(reduce(operator.__and__, self.rx_signals))
]
# FIXME: Add a test for the shared UART