Merge pull request #29 from probe-rs/fix-swd-sequence-and-swj-pins

Fix swd sequence and swj pins

Author: korken89

Cargo.lock

@@ -2,7 +2,7 @@
 authors = ["Emil Fresk <[email protected]>"]
 edition = "2021"
 name = "rusty-probe"
-version = "0.2.0"
+version = "0.3.0"
 
 [dependencies]
 bitflags = "1.3.2"
@@ -19,7 +19,7 @@ embedded-hal-02 = { package = "embedded-hal", version = "0.2.7", features = ["un
 panic-probe = { version = "0.3.0", features = ["print-defmt"] }
 replace_with = { version = "0.1.7", default-features = false, features = ["panic_abort"] }
 usbd-serial = "0.2.0"
-dap-rs = { git = "https://github.com/probe-rs/dap-rs.git", branch = "master", features = ["defmt"] }
+dap-rs = { version = "0.2.0", features = ["defmt"] }
 git-version = "0.3.5"
 pio-proc = "0.2.1"
 pio = "0.2.1"

Cargo.toml

@@ -132,7 +132,29 @@ impl swj::Dependencies<Swd, Jtag> for Context {
             }
         }
 
-        self.delay.delay_ticks(self.cycles_per_us * wait_us);
+        // Delay until desired output state or timeout.
+        let mut last = self.delay.get_current();
+        for _ in 0..wait_us {
+            last = self.delay.delay_ticks_from_last(self.cycles_per_us, last);
+
+            // If a pin is selected, make sure its output equals the desired output state, or else
+            // continue waiting.
+            let swclk_not_in_desired_state = mask.contains(swj::Pins::SWCLK)
+                && output.contains(swj::Pins::SWCLK) != self.swclk.is_high();
+            let swdio_not_in_desired_state = mask.contains(swj::Pins::SWDIO)
+                && output.contains(swj::Pins::SWDIO) != self.swdio.is_high();
+            let nreset_not_in_desired_state = mask.contains(swj::Pins::NRESET)
+                && output.contains(swj::Pins::NRESET) != self.nreset.is_high();
+
+            if swclk_not_in_desired_state
+                || swdio_not_in_desired_state
+                || nreset_not_in_desired_state
+            {
+                continue;
+            }
+
+            break;
+        }
 
         let mut ret = swj::Pins::empty();
         ret.set(swj::Pins::SWCLK, self.swclk.is_high());
@@ -326,6 +348,37 @@ impl swd::Swd<Context> for Swd {
         Ok(())
     }
 
+    fn write_sequence(&mut self, mut num_bits: usize, data: &[u8]) -> swd::Result<()> {
+        self.0.swdio_to_output();
+        let mut last = self.0.delay.get_current();
+
+        for b in data {
+            let bit_count = core::cmp::min(num_bits, 8);
+            for i in 0..bit_count {
+                self.write_bit((b >> i) & 0x1, &mut last);
+            }
+            num_bits -= bit_count;
+        }
+
+        Ok(())
+    }
+
+    fn read_sequence(&mut self, mut num_bits: usize, data: &mut [u8]) -> swd::Result<()> {
+        self.0.swdio_to_input();
+        let mut last = self.0.delay.get_current();
+
+        for b in data {
+            let bit_count = core::cmp::min(num_bits, 8);
+            for i in 0..bit_count {
+                let bit = self.read_bit(&mut last);
+                *b |= bit << i;
+            }
+            num_bits -= bit_count;
+        }
+
+        Ok(())
+    }
+
     fn set_clock(&mut self, max_frequency: u32) -> bool {
         trace!("SWD set clock: freq = {}", max_frequency);
         self.0.process_swj_clock(max_frequency)

src/dap.rs

@@ -4,7 +4,7 @@ use crate::systick_delay::Delay;
 use crate::{dap, usb::ProbeUsb};
 use core::mem::MaybeUninit;
 use dap_rs::usb_device::class_prelude::UsbBusAllocator;
-use embedded_hal::digital::{InputPin, OutputPin};
+use embedded_hal::digital::{InputPin, OutputPin, StatefulOutputPin};
 use embedded_hal::pwm::SetDutyCycle;
 use embedded_hal_02::adc::OneShot;
 use replace_with::replace_with_or_abort_unchecked;
@@ -303,13 +303,11 @@ where
         }
     }
 
-    /// Note: This function panics if the pin is in the wrong mode.
+    /// Note: If the pin is an output this will only reflect the set state, NOT electrical state.
     pub fn is_high(&mut self) -> bool {
         match self {
             DynPin::Input(i) => i.is_high() == Ok(true),
-            DynPin::Output(_) => {
-                defmt::panic!("Input operation on output pin");
-            }
+            DynPin::Output(o) => o.is_set_high() == Ok(true),
         }
     }
 }