use previous working dac code + set linien off

fast-servo/pyfastservo/common.py

@@ -22,8 +22,8 @@ MAP_SIZE = 0x1000
 MAP_MASK = 0xFFF
 PAGESIZE = 0x1000
 
-# LINIEN_OFFSET = 0x0
+LINIEN_OFFSET = 0x0
-LINIEN_OFFSET = 0x300000
+# LINIEN_OFFSET = 0x300000
 
 # ----------------------------------------------------------------
 # FRONT PANEL LEDS REGISTER ADDRESSES

fast-servo/pyfastservo/dac.py

@@ -1,24 +1,10 @@
-# This file is part of Fast Servo Software Package.
-#
-# Copyright (C) 2023 Jakub Matyas
-# Warsaw University of Technology <jakubk.m@gmail.com>
-# SPDX-License-Identifier: GPL-3.0-or-later
-#
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-# 
-# This program is distributed in the hope that it will be useful, 
-# but WITHOUT ANY WARRANTY; without even the implied warranty of 
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program. If not, see <https://www.gnu.org/licenses/>.
-
 import mmap
 import os
+import logging
+import time
+
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
 
 import spidev
 from pyfastservo.common import (
@@ -38,54 +24,153 @@ MAIN_DAC_DEVICE = 0
 DAC_VERSION = 0x0A
 
 
-def main_dac_init():
+def spi_write(spi, address, value):
-    spi = spidev.SpiDev()
+    spi.xfer2([address, value])
 
+def spi_read(spi, address):
+    rx_buffer = spi.xfer2([0x80 | address, 0x00])
+    return rx_buffer[1]
+
+def hard_reset(spi):
+    spi_write(spi, 0x00, 0x10)  # Software reset
+    spi_write(spi, 0x00, 0x00)  # Release software reset
+    spi_read(spi, 0x00)         # Read reset address (necessary for reset to take effect)
+
+def check_version(spi):
+    version = spi_read(spi, 0x1F)
+    if version == DAC_VERSION:
+        print(f"Verified DAC version: 0x{version:02X}")
+    else:
+        print(f"Unrecognized device version: 0x{version:02X}")
+
+def set_data_control_and_output_mode(spi, mode='differential'):
     try:
-        spi.open(MAIN_DAC_BUS, MAIN_DAC_DEVICE)
+        current_reg = spi_read(spi, 0x02)
-        spi.max_speed_hz = 5000
+        logger.info(f"Current data control register value: 0x{current_reg:02X}")
-        spi.mode = 0b00  # CPOL = 0 CPHA = 0
-        spi.cshigh = False
 
-        spi_buffer = [0x00, 0x10]  # software reset
+        new_reg = 0xB4
-        spi.xfer2(spi_buffer)
 
-        spi_buffer = [0x00, 0x00]  # release software reset
+        if mode == 'differential':
-        spi.xfer2(spi_buffer)
+            new_reg &= ~0x03
+        elif mode == 'single_ended':
+            new_reg = (new_reg & ~0x01) | 0x02
+        else:
+            logger.error(f"Invalid output mode: {mode}")
+            return
 
-        spi_buffer = [
+        spi_write(spi, 0x02, new_reg)
-            0x80,
-            0x00,
-        ]  # for some reason it is needed to read the reset address for reset to actually reset
-        rx_buffer = spi.xfer2(spi_buffer)
 
-        spi_buffer = [0x9F, 0x00]  # hardware version
+        verify_reg = spi_read(spi, 0x02)
-        rx_buffer = spi.xfer2(spi_buffer)
+        if verify_reg == new_reg:
-        if rx_buffer[1] != DAC_VERSION:
+            logger.info(f"Data control set and output mode successfully set to {mode}")
-            print(f"Unrecognized device: 0x{rx_buffer[1]:02X}")
+            logger.info(f"New data control register value: 0x{verify_reg:02X}")
+        else:
+            logger.error(f"Failed to set data control and output mode. Expected: 0x{new_reg:02X}, Got: 0x{verify_reg:02X}")
+    except Exception as e:
+        logger.error(f"Error setting data control and output mode: {e}")
 
-        print("=== Contents of spi buffer after DAC VERSION read back: ===")
-        print(f"0x{rx_buffer[0]:02X}{rx_buffer[1]:02X}")
 
-        spi_buffer = [0x82, 00]
+def wait_for_clock_sync(spi):
-        rx_buffer = spi.xfer2(spi_buffer)
+    max_attempts = 10
-        print(f"0x{rx_buffer[0]:02X}{rx_buffer[1]:02X}")
+    for attempt in range(max_attempts):
+        clkmode = spi_read(spi, 0x14)
+        if not clkmode & 0x10:
+            print(f"Clock synchronized after {attempt + 1} attempts")
+            break
+        if attempt == max_attempts - 1:
+            print("Warning: Clock synchronization not achieved")
+        time.sleep(0.001)
 
-        # set to 2's complement and I to be first of pair on data input pads
-        spi_buffer = [0x02, 0xB4]
-        rx_buffer = spi.xfer2(spi_buffer)
-        spi_buffer = [0x82, 00]
-        rx_buffer = spi.xfer2(spi_buffer)
-        print(f"0x{rx_buffer[0]:02X}{rx_buffer[1]:02X}")
 
-        for i in range(10):
+def enable_dac_outputs(spi):
-            spi_buffer = [0x94, 0x00]
+    try:
-            rx_buffer = spi.xfer2(spi_buffer)
+        # Read current power-down register value
-            print(f"0x{rx_buffer[0]:02X}{rx_buffer[1]:02X}")
+        power_down_reg = spi_read(spi, 0x01)
+        logger.info(f"Current power-down register value: 0x{power_down_reg:02X}")
 
-    finally:
+        if not (power_down_reg & ((1 << 4) | (1 << 3))):
-        spi.close()
+            logger.info("DAC outputs are already enabled")
+            return
 
+        new_power_down_reg = power_down_reg & ~((1 << 4) | (1 << 3))
+        spi_write(spi, 0x01, new_power_down_reg)
+
+        # Verify the write operation
+        verify_power_down_reg = spi_read(spi, 0x01)
+        if verify_power_down_reg == new_power_down_reg:
+            logger.info("DAC outputs successfully enabled")
+        else:
+            logger.error(f"Failed to enable DAC outputs. Expected: 0x{new_power_down_reg:02X}, Got: 0x{verify_power_down_reg:02X}")
+    except Exception as e:
+        logger.error(f"Error enabling DAC outputs: {e}")
+
+
+def set_dac_constant_output(value=0xFFFF):
+    try:
+        max_value = 0x3FFF  # 14-bit maximum (2^14 - 1)
+        value = min(value, max_value)
+        
+        # Split the value into high and low words
+        low_word_value = value & 0xFF
+        high_word_value = (value >> 8) & 0x3F
+        
+        # Write to Channel 0
+        write_to_memory(CH0_HIGH_WORD_ADDR, high_word_value)
+        write_to_memory(CH0_LOW_WORD_ADDR, low_word_value)
+        
+        # Write to Channel 1
+        write_to_memory(CH1_HIGH_WORD_ADDR, high_word_value)
+        write_to_memory(CH1_LOW_WORD_ADDR, low_word_value)
+        
+        logger.info(f"DAC outputs set to constant value: 0x{value:04X}")
+        logger.info("Please verify the output using an oscilloscope")
+        
+    except Exception as e:
+        logger.error(f"Error setting DAC constant output: {e}")
+
+
+def configure_dac_for_hardware(spi):
+    try:
+        # Enable internal reference
+        power_down_reg = spi_read(spi, 0x01)
+        power_down_reg &= ~(1 << 0)  # Clear EXTREF bit for internal reference
+        spi_write(spi, 0x01, power_down_reg)
+        logger.info("Internal reference enabled")
+
+        # Set RREF to default 10 kΩ for 1.0V reference
+        spi_write(spi, 0x0D, 0x00)
+        logger.info("RREF set to 10 kΩ for 1.0V reference")
+
+        # Enable on-chip IRSET and QRSET
+        irset_value = 0xA0                  # 10100000
+        spi_write(spi, 0x04, irset_value)   # IRSET
+        spi_write(spi, 0x07, irset_value)   # QRSET
+
+        # Disable internal termination resistors
+        ircml_value = 0x00
+        spi_write(spi, 0x05, ircml_value)  # IRCML
+        spi_write(spi, 0x08, ircml_value)  # QRCML
+
+        spi_write(spi, 0x02, 0xB4)
+
+        # Verify settings
+        irset_read = spi_read(spi, 0x04)
+        qrset_read = spi_read(spi, 0x07)
+        ircml_read = spi_read(spi, 0x05)
+        qrcml_read = spi_read(spi, 0x08)
+        data_control_read = spi_read(spi, 0x02)
+        
+        if (irset_read == irset_value and qrset_read == irset_value and
+            ircml_read == ircml_value and qrcml_read == ircml_value and
+            data_control_read == 0xB4):
+            logger.info("DAC configured for 20mA output with external termination")
+        else:
+            logger.error(f"DAC configuration failed. IRSET: 0x{irset_read:02X}, QRSET: 0x{qrset_read:02X}, "
+                         f"IRCML: 0x{ircml_read:02X}, QRCML: 0x{qrcml_read:02X}, "
+                         f"Data Control: 0x{data_control_read:02X}")
+
+    except Exception as e:
+        logger.error(f"Error configuring DAC: {e}")
 
 def read_from_memory(address, n_bytes):
     assert n_bytes <= 4
@@ -152,31 +237,49 @@ def power_down(channel, power_down=True):
     reg_contents = read_from_memory(CTRL_ADDR, 1)[0]
     print(f"REG contents: 0b{reg_contents:03b}")
 
+def main_dac_init():
+    spi = spidev.SpiDev()
 
-def write_sample(channel, sample):
+    try:
-    assert channel in (0, 1)
+        spi.open(MAIN_DAC_BUS, MAIN_DAC_DEVICE)
-    if channel == 0:
+        spi.max_speed_hz = 5000
-        addresses = [CH0_HIGH_WORD_ADDR, CH0_LOW_WORD_ADDR]
+        spi.mode = 0b00  # CPOL = 0 CPHA = 0
-    else:
+        spi.cshigh = False
-        addresses = [CH1_HIGH_WORD_ADDR, CH1_LOW_WORD_ADDR]
 
-    low_word_value = sample & 0xFF
+        hard_reset(spi)
-    high_word_value = (sample >> 8) & 0x3F
+        check_version(spi)
-    values = [high_word_value, low_word_value]
-    for addr, value in zip(addresses, values):
-        write_to_memory(addr, value)
 
+        configure_dac_for_hardware(spi)
+        set_data_control_and_output_mode(spi, 'differential')
+        wait_for_clock_sync(spi)
+        enable_dac_outputs(spi)
 
-def write_ramp():
-    signal = [i for i in range(16384)]
-
-    for value in signal:
-        write_sample(0, value)
-
-def main():
-    main_dac_init()
         power_down(0, False)
         power_down(1, False)
 
+        manual_override(True)
+
+        set_dac_constant_output(0x1FFF)
+
+        # Verify control register
+        reg_contents = read_from_memory(CTRL_ADDR, 1)[0]
+        logger.info(f"Control register contents after setting: 0b{reg_contents:03b}")
+
+        # Verify channel settings
+        ch0_high = read_from_memory(CH0_HIGH_WORD_ADDR, 1)[0]
+        ch0_low = read_from_memory(CH0_LOW_WORD_ADDR, 1)[0]
+        ch1_high = read_from_memory(CH1_HIGH_WORD_ADDR, 1)[0]
+        ch1_low = read_from_memory(CH1_LOW_WORD_ADDR, 1)[0]
+        logger.info(f"Channel 0: 0x{ch0_high:02X}{ch0_low:02X}, Channel 1: 0x{ch1_high:02X}{ch1_low:02X}")
+    except Exception as e:
+        print(f"Error initializing DAC: {e}")
+
+    finally:
+        spi.close()
+
+
+def main():
+    main_dac_init()
+    
 if __name__ == "__main__":
     main()