AP_HAL_ChibiOS: allow setup for low noise clock mismatch tolerant UAR…

…T line
ArduPilot · Jul 17, 2024 · cf52c86 · cf52c86
1 parent c3e6236
commit cf52c86
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Showing 2 changed files with 12 additions and 4 deletions.
diff --git a/libraries/AP_HAL_ChibiOS/UARTDriver.cpp b/libraries/AP_HAL_ChibiOS/UARTDriver.cpp
@@ -461,6 +461,11 @@ void UARTDriver::_begin(uint32_t b, uint16_t rxS, uint16_t txS)
                 sercfg.cr3 |= USART_CR3_DMAT;
             }
             sercfg.irq_cb = rx_irq_cb;
+            if (sdef.low_noise_line) {
+                // we can mark UART to sample on one bit instead of default 3 bits
+                // this allows us to be slightly less sensitive to clock differences
+                sercfg.cr3 |= USART_CR3_ONEBIT;
+            }
 #endif // HAL_UART_NODMA
             if (!(sercfg.cr2 & USART_CR2_STOP2_BITS)) {
                 sercfg.cr2 |= USART_CR2_STOP1_BITS;

diff --git a/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py b/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py
@@ -1899,12 +1899,12 @@ def write_UART_config(self, f):
 
             if dev.startswith('OTG2'):
                 f.write(
-                    '#define HAL_%s_CONFIG {(BaseSequentialStream*) &SDU2, 2, true, false, 0, 0, false, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, UINT8_MAX}\n' % dev)  # noqa
+                    '#define HAL_%s_CONFIG {(BaseSequentialStream*) &SDU2, 2, true, false, 0, 0, false, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, UINT8_MAX, false}\n' % dev)  # noqa
                 OTG2_index = serial_list.index(dev)
                 self.dual_USB_enabled = True
             elif dev.startswith('OTG'):
                 f.write(
-                    '#define HAL_%s_CONFIG {(BaseSequentialStream*) &SDU1, 1, true, false, 0, 0, false, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, UINT8_MAX}\n' % dev)  # noqa
+                    '#define HAL_%s_CONFIG {(BaseSequentialStream*) &SDU1, 1, true, false, 0, 0, false, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, UINT8_MAX, false}\n' % dev)  # noqa
             else:
                 need_uart_driver = True
                 f.write(
@@ -1943,8 +1943,11 @@ def get_RTS_alt_function():
                             if s not in lib.AltFunction_map:
                                 return "UINT8_MAX"
                             return lib.AltFunction_map[s]
-
-                f.write("%s}\n" % get_RTS_alt_function())
+                low_noise = 'false'
+                rx_port = dev + '_RX'
+                if rx_port in self.bylabel and self.bylabel[rx_port].has_extra('LOW_NOISE'):
+                    low_noise = 'true'
+                f.write("%s, %s}\n" % (get_RTS_alt_function(), low_noise))
 
         if have_rts_cts:
             f.write('#define AP_FEATURE_RTSCTS 1\n')