From 607da8a8222e00709b357a47a7d4b525eb83fc74 Mon Sep 17 00:00:00 2001
From: linuswck <linuswck@m-labs.hk>
Date: Wed, 20 Mar 2024 17:24:29 +0800
Subject: [PATCH] ld: Add a delay before turning on LD PWR - DAC output might
 not drop to 0V before PWR is being turned on - Thus, it might drive
 nondeterministic current into the laser diode during pwr up

---
 src/laser_diode/laser_diode.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/laser_diode/laser_diode.rs b/src/laser_diode/laser_diode.rs
index cc57b77..6143d5b 100644
--- a/src/laser_diode/laser_diode.rs
+++ b/src/laser_diode/laser_diode.rs
@@ -121,6 +121,8 @@ impl LdDrive{
         let prev_i_set = self.settings.ld_drive_current;
         LdCurrentOutCtrlTimer::reset();        
         let _ = self.ctrl.set_i(ElectricCurrent::new::<milliampere>(0.0), Settings::LD_DRIVE_TRANSIMPEDANCE, Settings::DAC_OUT_V_MAX);
+        // Wait for the DAC to reset its voltage back to 0V
+        sleep(10);
         LdPwrExcProtector::pwr_on_and_arm_protection();
         // Wait for LD Power Supply to start up before driving current to laser diode
         sleep(30);