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Linduino
1.3.0
Linear Technology Arduino-Compatible Demonstration Board
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Linear Technology DC1466 Demonstration Board. More...
Linear Technology DC1466 Demonstration Board.
LTC2636: Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference.
Linear Technology DC1488 Demonstration Board. LTC2634: Quad 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference.
NOTES Setup: Set the terminal baud rate to 115200 and select the newline terminator. The program displays calculated voltages which are based on the voltage of the reference used, be it internal or external. A precision voltmeter is needed to verify the actual measured voltages against the calculated voltage displayed. If an external reference is used, a precision voltage source is required to apply the external reference voltage. A precision voltmeter is also required to measure the external reference voltage. No external power supply is required. Any assembly option may be used: DC1466A-A, DC1466A-B, DC1466A-C, DC1466A-D. Explanation of Commands: 1- Select DAC: Select one of four DACs to test : A, B, C, D. 2- Write to DAC input register: Value is stored in the DAC for updating later, allowing multiple channels to be updated at once, either through a software "Update All" command or by asserting the LDAC# pin. User will be prompted to enter either a code in hex or decimal, or a voltage. If a voltage is entered, a code will be calculated based on the active scaling and reference parameters - ideal values if no calibration was ever stored. 3- Write and Update: Similar to item 1, but DAC is updated immediately. 4- Update DAC: Copies the value from the input register into the DAC Register. Note that a "write and update" command writes the code to BOTH the input register and DAC register, so subsequent "update" commands will simply re-copy the same data (no change in output.) 5- Power Down DAC: Disable DAC output. Power supply current is reduced. DAC code present in DAC registers at time of shutdown are preserved. 6- Set reference mode, either internal or external: Selecting external mode prompts for the external reference voltage, which is used directly if no individual DAC calibration is stored. The selection and entered voltage are stored to EEPROM so it is persistent across reset / power cycles. USER INPUT DATA FORMAT: decimal : 1024 hex : 0x400 octal : 02000 (leading 0 "zero") binary : B10000000000 float : 1024.0
http://www.linear.com/product/LTC2636 http://www.linear.com/product/LTC2634
http://www.linear.com/product/LTC2636#demoboards http://www.linear.com/product/LTC2634#demoboards
Copyright 2018(c) Analog Devices, Inc.
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Definition in file DC1466.ino.
Go to the source code of this file.
Functions | |
static void | restore_calibration () |
Read stored calibration parameters from nonvolatile EEPROM on demo board. More... | |
static void | print_title () |
Prints the title block when program first starts. More... | |
static void | print_prompt (int16_t selected_dac) |
Prints main menu. More... | |
static int16_t | prompt_voltage_or_code () |
Prompt user to enter a voltage or digital code to send to DAC. More... | |
static uint16_t | get_voltage (float LTC2636_lsb, int16_t LTC2636_offset) |
Get voltage from user input, calculate DAC code based on lsb, offset. More... | |
static uint16_t | get_code () |
Get code to send to DAC directly, in decimal, hex, or binary. More... | |
static void | menu_1_select_dac (int16_t *selected_dac) |
Select which DAC to operate on. More... | |
static void | menu_2_write_to_input_register (int16_t selected_dac) |
Write data to input register, but do not update DAC output. More... | |
static void | menu_3_write_and_update_dac (int16_t selected_dac) |
Write data to DAC register (which updates output immediately) More... | |
static void | menu_4_update_power_up_dac (int16_t selected_dac) |
Update DAC with data that is stored in input register, power up if sleeping. More... | |
static void | menu_5_power_down_dac (int16_t selected_dac) |
Power down DAC. More... | |
static void | menu_6_set_reference_mode (void) |
Set reference mode and store to EEPROM. More... | |
static int8_t | menu_7_calibrate_dacs () |
Calibrate all DACs by measuring two known outputs. More... | |
static void | setup () |
Initialize Linduino. More... | |
static void | loop () |
Repeats Linduino loop. More... | |
static int8_t | calibrate_dac (uint8_t index) |
Calibrate the selected DAC using a voltmeter. More... | |
Macros | |
#define | REF_INTERNAL LTC2636_CMD_INTERNAL_REFERENCE |
Stored reference state is Internal. More... | |
#define | REF_EXTERNAL LTC2636_CMD_EXTERNAL_REFERENCE |
Stored reference state is External. More... | |
Enumerations | |
enum | { PROMPT_VOLTAGE = 0, PROMPT_CODE = 1 } |
Used to keep track to print voltage or print code. More... | |
Variables | |
static uint8_t | demo_board_connected |
Set to 1 if the board is connected. More... | |
static uint8_t | shift_count |
The data align shift count. More... | |
static uint8_t | reference_mode |
Tells whether to set internal or external reference. More... | |
static float | reference_voltage |
Reference voltage, either internal or external. More... | |
static int16_t | LTC2636_offset [9] |
DAC offset - index 8 for "all DACs". More... | |
static float | LTC2636_lsb [9] |
The LTC2636 lsb - index 8 for "all DACs". More... | |
static uint8_t | num_of_channels = 8 |
const uint8_t | address_map [9] = {LTC2636_DAC_A, LTC2636_DAC_B, LTC2636_DAC_C, LTC2636_DAC_D, LTC2636_DAC_E, LTC2636_DAC_F, LTC2636_DAC_G, LTC2636_DAC_H, LTC2636_DAC_ALL} |
Lookup table for DAC address. More... | |
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Calibrate the selected DAC using a voltmeter.
The routine does a linear curve fit given two data points.
Definition at line 488 of file DC1466.ino.
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Get code to send to DAC directly, in decimal, hex, or binary.
Definition at line 473 of file DC1466.ino.
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Get voltage from user input, calculate DAC code based on lsb, offset.
Definition at line 459 of file DC1466.ino.
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Repeats Linduino loop.
Definition at line 175 of file DC1466.ino.
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Select which DAC to operate on.
Definition at line 224 of file DC1466.ino.
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Write data to input register, but do not update DAC output.
Definition at line 236 of file DC1466.ino.
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Write data to DAC register (which updates output immediately)
Definition at line 248 of file DC1466.ino.
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Update DAC with data that is stored in input register, power up if sleeping.
Definition at line 262 of file DC1466.ino.
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Power down DAC.
Definition at line 275 of file DC1466.ino.
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Set reference mode and store to EEPROM.
Definition at line 288 of file DC1466.ino.
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Calibrate all DACs by measuring two known outputs.
Definition at line 308 of file DC1466.ino.
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Prints main menu.
Definition at line 411 of file DC1466.ino.
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Prints the title block when program first starts.
Definition at line 396 of file DC1466.ino.
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Prompt user to enter a voltage or digital code to send to DAC.
Definition at line 443 of file DC1466.ino.
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Read stored calibration parameters from nonvolatile EEPROM on demo board.
Definition at line 321 of file DC1466.ino.
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Initialize Linduino.
Definition at line 157 of file DC1466.ino.
#define REF_EXTERNAL LTC2636_CMD_EXTERNAL_REFERENCE |
Stored reference state is External.
Definition at line 117 of file DC1466.ino.
#define REF_INTERNAL LTC2636_CMD_INTERNAL_REFERENCE |
Stored reference state is Internal.
Definition at line 116 of file DC1466.ino.
anonymous enum |
Used to keep track to print voltage or print code.
Enumerator | |
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PROMPT_VOLTAGE | 0 |
PROMPT_CODE | 1 |
Definition at line 150 of file DC1466.ino.
const uint8_t address_map[9] = {LTC2636_DAC_A, LTC2636_DAC_B, LTC2636_DAC_C, LTC2636_DAC_D, LTC2636_DAC_E, LTC2636_DAC_F, LTC2636_DAC_G, LTC2636_DAC_H, LTC2636_DAC_ALL} |
Lookup table for DAC address.
Allows the "All DACs" address to be indexed right after DAC D in loops. This technique is very useful for devices with non-monotonic channel addresses. Map entered option 0..2 to DAC address
Definition at line 147 of file DC1466.ino.
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Set to 1 if the board is connected.
Definition at line 136 of file DC1466.ino.
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The LTC2636 lsb - index 8 for "all DACs".
Definition at line 141 of file DC1466.ino.
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DAC offset - index 8 for "all DACs".
Definition at line 140 of file DC1466.ino.
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Definition at line 142 of file DC1466.ino.
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Tells whether to set internal or external reference.
Definition at line 138 of file DC1466.ino.
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Reference voltage, either internal or external.
Definition at line 139 of file DC1466.ino.
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The data align shift count.
For 12-bits=4, 10-bits=6, 8-bits=8
Definition at line 137 of file DC1466.ino.