28023 Parallax Inc, 28023 Datasheet - Page 3

• Manufacturer Part Number: 28023
• Description: CONTROLLER 16SERVO MOTOR CONTROL
• Manufacturer: Parallax Inc

Specifications of 28023

• Lead Free Status: Contains lead
• Main Purpose: Power Management, Motor Control
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: BASIC Stamp® or Javelin Modules
• Primary Attributes: Servo Controller
• Secondary Attributes: 16 channels
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 28023PAR

Follow the instructions in this document when making connections to the PSC. To power up your PSC,
slide the power switch on the BOE to the “2” position. You should see the red LED illuminate on the PSC
as well as the green LED light on the BOE.
Serial Command Format
The PSC supports several commands that are sent to it via RS-232 serial protocol. The voltage swing of
this serial line is 0-5 VDC (TTL level). Each serial command must be preceded with an exclamation point,
“!”, and the pair of letters, “SC”.
When your PSC starts up, the default baudrate is 2400 N 8 2, (no parity, eight data bits, two stop bits)
true data, open-drain (driven low, pulled high). The exclamation point is used in some AppMods to
determine the incoming baudrate, thereby supporting a feature called Auto-Baud. The PSC does not
support Auto-Baud. The “SC” portion is an identifier that pertains to the PSC. Together, the “!” and the
“SC” form a preamble, “!SC”. The preamble serves to distinguish commands for the PSC from other
messages on the serial I/O line, and allow different types of AppMods to use the same serial line.
After the preamble is sent, the command and associated parameters are sent. The eighth and final
character sent is a $0D, (CR), used to terminate the string. If the command causes the PSC to reply, a
three-byte reply is sent after a 1.5 mS delay.
Parallax, Inc. • Parallax Servo Controller – Rev B ver2.4 (#28023) • 1/2005
© 2004
www.parallax.com
Figure 3: Parallax Servo Controller, typical Connections.
standard servo
Servo Controller
7.5 VDC max
www.parallax.com
Rev A
standard servo
Battery
9 Vdc
Sout
Sin
Vss
ATN
P0
P1
P2
P3
P4
P5
P6
P7
www.parallax.com/sic
1
U1
6-9VDC
Vin
Vss
Rst
Vdd
P15
P14
P13
P12
P11
P10
P9
P8
TM
Vss
P0
P2
P4
P6
P8
P10
P12
P14
Vdd
0 1 2
Reset
X1
Vss
P1
P3
P5
P7
P9
P11
P13
P15
Vin
Pwr
P15
P14
P13
P12
P11
P10
P9
P8
P7
P6
P5
P4
P3
P2
P1
P0
X2
X3
Board of Education
Rev C
Vdd
15 14
X4
Vdd
Vin
© 2000-2003
13 12
X5
Vss
Red
Black
3