27961 Parallax Inc, 27961 Datasheet - Page 10

• Manufacturer Part Number: 27961
• Description: MODULE MOTOR MIND SIP
• Manufacturer: Parallax Inc

Specifications of 27961

• Product: Microcontroller Accessories
• Operating Supply Voltage: 6 to 36 V
• Board Size: 30.48 mm x 25.4 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Motor Mind B enhanced
Data Sheet
4.0 Communication Protocol
4.1 Overview
The MMBe is controlled via a serial data interface. The protocol requires data to be received at TTL
levels (0V = logic 0, 5V = logic 1), 8 data bits, no parity bit, 1 stop bit (8N1). Data is arranged least
significant bit first (LSB). The default baud rate is 2.4KBPS, but using the CHANGE_BAUD command
allows the user to toggle the baud rate between 2.4KBPS and 9.6KBPS. Each byte of data should be
sent with no more than 500us between bytes. A special note regarding the TM (data to master) pin is
required. This pin has a 270
resistors are used external to the MMBe they should be 10KΩ or larger (FYI: pull-up/down resistors are unnecessary
on the TM pin).
Serial commands are sent starting with the sync byte (decimal 85, hexadecimal 0x55), the command
byte, and any additional data required by the command. No checksum is required.
A typical application would have some master controller (a popular one is the Parallax BASIC Stamp,
www.parallax.com). But you may also control it via a PC serial COMM port. With a PC the data voltages
must be converted from RS232 (+12V = logic 0, -12V = logic 1) to TTL levels. Figures 3 and 4 are
examples of the connections required for these applications.
DB9-M or DB9-F
10
11
12
1
2
3
4
5
6
7
8
9
1
6
2
7
3
8
4
9
5
TX
RX
ATN
GND
P0
P1
P2
P3
P4
P5
P6
P7
BS2_BS2SX
0.1 uF
5VDC
PWR
GND
0.1 uF
0.1 uF
RES
+5V
P15
P14
P13
P12
P11
P10
P9
P8
Figure 4: Parallax BASIC Stamp Connection Schematic
12VDC
24
23
22
21
20
19
18
17
16
15
14
13
Phone: [phone] - www.solutions-cubed.com
14
13
16
Figure 3: PC Serial Port Connection Schematic
7
8
4
5
2
Ω series resistor to protect this output from shorting ground. If pull-up or pull-down
Motor Control System - Solutions Cubed, LLC
232_OUT1
232_IN1
232_OUT2
232_IN2
C2+
C2-
VCC
V+
MAX232A
TTL_OUT1
TTL_OUT2
TTL_IN1
TTL_IN2
VSS
C1+
MOTOR
C1-
V-
11
12
10
9
1
3
6
15
DATA TO MASTER UNIT
DATA FROM MASTER UNIT
M+
M-
0.1 uF
0.1 uF
MOTOR
DATA TO MASTER UNIT
DATA FROM MASTER UNIT
M+
M-
+
5VDC
12VDC
270uF
+
5VDC
12VDC
1
2
3
4
5
6
7
8
9
270uF
5V
GND
TM
FM
_BRAKE
TACH_IN
MOTOR-
MOTOR+
VMOTOR
Solutions Cubed
MMBe
1
2
3
4
5
6
7
8
9
5V
GND
TM
FM
_BRAKE
TACH_IN
MOTOR-
MOTOR+
VMOTOR
Page 10
MMBe