From 6b891065787ae6dbb0c578cb97a3a51f488be248 Mon Sep 17 00:00:00 2001
From: David Nadlinger <code@klickverbot.at>
Date: Sat, 28 Jul 2018 23:45:48 +0100
Subject: [PATCH] ad53xx: Avoid sporadic RTIOUnderflow in init()
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I observed sporadic RTIO underflows on Kasli before, by ~2.5 µs,
so 5 µs extra slack should be plenty. No underflows since.
---
 artiq/coredevice/ad53xx.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/artiq/coredevice/ad53xx.py b/artiq/coredevice/ad53xx.py
index 21c85a1d4..b19c246f5 100644
--- a/artiq/coredevice/ad53xx.py
+++ b/artiq/coredevice/ad53xx.py
@@ -171,7 +171,7 @@ class AD53xx:
             ctrl = self.read_reg(channel=0, op=AD53XX_READ_CONTROL)
             if ctrl & 0b10000:
                 raise ValueError("DAC over temperature")
-            delay(10*us)
+            delay(15*us)
         self.bus.write(  # enable power and overtemperature shutdown
             (AD53XX_CMD_SPECIAL | AD53XX_SPECIAL_CONTROL | 0b0010) << 8)
         if not blind: