Juno Step Motor Control IC User Guide
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6
6.Juno IC Configuration in the
Production Application
In This Chapter
Loading the NVRAM
Analog Signal Calibration in the Production Application
Each Juno IC, before undertaking step motor control, must be programmed with control parameter settings appropriate
for the application that it will be used in. These control parameters include quantities such as PWM (Pulse Width
Modulation) frequency, current gains, safety thresholds, and more.
Correct values for these parameters are most easily determined by PMD Corp.’s Pro-Motion software, specifically via
the Axis Wizard setup sequence. The axis wizard steps the user through a series of set up and verification pages, finally
resulting in control parameter settings tailored for that user application.
Once the control parameters are determined the user has two choices for how they can be loaded into the active control
registers of the Juno IC when it is in the production PCB; they can be stored permanently into the Juno IC’s internal
NVRAM (non-volatile memory) and auto-loaded at power-up, or they can be loaded at each power-up by an on-board
microprocessor connected to the Juno IC via its serial port.
Storing the NVRAM data into the Juno IC is discussed in the next section,
Applications that load the control registers via an on-board microprocessor use specially formatted host commands sent
over the serial port. For more information refer to the
Juno Velocity & Torque Control IC User Guide
.
6.1
Loading the NVRAM
6.1.1
NVRAM Programming via Juno DK IC Socket
The 64-pin TQFP package Juno DK includes an IC socket that can be used to program the NVRAM on 64-pin Juno
ICs prior to soldering into the user’s production PCB. Pro-Motion as well as a more compact programming executive
available from PMD Corp. supports script files to program the Juno IC NVRAM. For more information on PMD Corp.
script files refer to
7.5.1, “Host Command Script Files.”
6.1.2
NVRAM Programming Via 3-pin UART Cable
An alternate NVRAM programming approach is to execute the NVRAM download by communicating to the Juno IC
after it is installed in the production PCB. This approach requires that each installed Juno IC have a 3-pin connector
installed on the production board. A technician plugs into this connector and performs the NVRAM download. To be
programmed the Juno IC must receive power, so this generally means the PCB power is turned on during this procedure.
To facilitate this approach PMD Corp. provides a dedicated USB to 3-pin UART programming cable (PMD Corp. Part
# CONN-USB-3P) with each Juno DK. This programming cable plugs into the PC’s USB port on one end and into a
The 56-pin VQFN Juno IC DK does not have a socket and therefore cannot be used to program the NVRAM of
production 56-pin VQFN Juno ICs.
