Intelligent Motion Systems MDrive AC Plus 34, Operating Instructions Manual

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MDriveAC Plus Microstepping Hardware - Revision R052506
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Part 2: Interfacing and Configuring
SECTION 2.4
Configuring the MDriveAC Plus Microstepping Using User-Defined SPI
The MDrive can be configured and operated through the end-user's SPI interface without using the IMS SPI Mo-
tor Interface software and optional parameter setup cable.
An example of when this might be used is in cases where the machine design requires parameter settings to be
changed on-the-fly by a software program or multiple system MDriveAC Plus Microstepping units parameter states
being written/read.
SPI Timing Notes
1. MSb (Most Significant bit) first and MSB (Most Significant Byte) first.
2. 8 bit bytes.
3. 25 kHz SPI Clock (SCK).
4. Data In (MOSI) on rising clock.
5. Data Out (MISO) on falling clock.
Figure 2.4.1: SPI Timing Diagram
Check Sum Calculation for SPI
The values in the example below are 8-bit binary hexadecimal conversions for the following SPI parameters:
MRC=25%, MHC=5%, MSEL=256, HCDT=500 mSec, WARNTEMP=80.
The Check Sum is calculated as follows:
(Hex) 80+19+05+00+00+01+F4+50
Sum = E3 1110 0011
1’s complement = 1C 0001 1100 (Invert)
2’s complement = 1D 0001 1101 (Add 1)
Send the check sum value of 1D
Note: 80 is always the first command on a write.
Note: Once a write is performed, a read needs to be performed to see if there is a fault. The fault is the last byte of
the read.