From 8446cccb4eb0ff139ae1fc9366e9d13b96e8dd1a Mon Sep 17 00:00:00 2001
From: Robert Jordens <rj@m-labs.hk>
Date: Thu, 13 Apr 2017 13:38:13 +0200
Subject: [PATCH] pdq2: mem_read

---
 artiq/coredevice/pdq2.py | 25 +++++++++++++++++++++----
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/artiq/coredevice/pdq2.py b/artiq/coredevice/pdq2.py
index 5410e7d2f..18ff1c773 100644
--- a/artiq/coredevice/pdq2.py
+++ b/artiq/coredevice/pdq2.py
@@ -35,7 +35,7 @@ class PDQ2:
         self.chip_select = chip_select
 
     @kernel
-    def setup_bus(self, write_div=4, read_div=15):
+    def setup_bus(self, write_div=24, read_div=64):
         """Configure the SPI bus and the SPI transaction parameters
         for this device. This method has to be called before any other method
         if the bus has been used to access a different device in the meantime.
@@ -64,7 +64,7 @@ class PDQ2:
         delay_mu(self.bus.ref_period_mu)  # get to 20ns min cs high
         self.bus.read_async()
         self.bus.set_xfer(self.chip_select, 16, 0)
-        return self.bus.input_async() & 0xff
+        return int(self.bus.input_async() & 0xff)  # FIXME: m-labs/artiq#713
 
     @kernel
     def write_config(self, reset=0, clk2x=0, enable=1,
@@ -94,7 +94,7 @@ class PDQ2:
         return self.read_reg(_PDQ2_ADR_FRAME, board)
 
     @kernel
-    def write_mem(self, mem, adr, data, board=0xf):
+    def write_mem(self, mem, adr, data, board=0xf):  # FIXME: m-labs/artiq#714
         self.bus.set_xfer(self.chip_select, 24, 0)
         self.bus.write((_PDQ2_CMD(board, 1, mem, 1) << 24) |
                        ((adr & 0x00ff) << 16) | (adr & 0xff00))
@@ -108,4 +108,21 @@ class PDQ2:
 
     @kernel
     def read_mem(self, mem, adr, data, board=0xf):
-        pass
+        self.bus.set_xfer(self.chip_select, 24, 8)
+        self.bus.write((_PDQ2_CMD(board, 1, mem, 0) << 24) |
+                       ((adr & 0x00ff) << 16) | (adr & 0xff00))
+        delay_mu(-self.bus.write_period_mu-3*self.bus.ref_period_mu)
+        self.bus.set_xfer(self.chip_select, 0, 16)
+        for i in range(len(data)//2):
+            self.bus.write(0)
+            delay_mu(-self.bus.write_period_mu-3*self.bus.ref_period_mu)
+            self.bus.read_async()
+            d = self.bus.input_async()
+            data[2*i] = (d >> 8) & 0xff
+            data[2*i + 1] = d & 0xff
+            return int(self.bus.input_async() & 0xff)  # FIXME: m-labs/artiq#713
+        delay_mu(self.bus.write_period_mu + self.bus.ref_period_mu)
+        # get to 20ns min cs high
+        self.bus.set_xfer(self.chip_select, 16, 0)
+
+       pass