General Description
The RPC-52 is a versatile embedded controller with digital and analog I/O and operator interfaces. It includes the RPBASIC-52 programming language which is an enhanced version of
BASIC-52. Single commands support opto, time, analog, and digital I/O functions, significantly speeding up program execution. Serial ports are now fully buffered. This ensures no missed incoming characters and
also "PRINT" statements execute faster. The RPC-52 operates at 22 MHz making it over twice as fast as other cards using the same language.
The RPC-52 is an "instant-on" system. It includes all
software and hardware so the system is fully operational "out of the box". You just supply +5V, a PC, cable, and a modem communications program.
Function Description
Digital I/O
Twenty-four
digital I/O lines allow connection to switches, LED's, opto modules, and other TTL type devices. Eight high current outputs drive small motors, solenoids, relays, and other devices requiring less than 200 mA at 50V. Use
the MPS-08, -16, or -24 to expand opto module capability. The "LINE" command controls individual outputs and reads inputs.
Analog I/O
You can use the RPC-52's analog I/O to measure pressure,
position, or temperature. Floating point math converts the results into "real" units for display. You can also log data into battery backed RAM for
analysis or retrieval later. The opto rack supports
optically isolated analog I/O using G5 modules.
The eight analog inputs have an input range of 0 to 5V. The "AIN" function returns a number from 0 to 1023 (10 bits) corresponding to its input
voltage. Conversion time is approximately 1 mS.
Two analog outputs generate a PWM output. Output voltage is 0 to 5V, unloaded. Resolution is within 0.5%. PWM is shared with two opto rack
positions. If analog output is desired, then a PWM output
is not available.
On-Card Opto Rack
An on-card opto rack supports G4 I/O and G5 analog input modules. You can add up to 24 additional G4 and G5
I/O modules using a MPS series opto rack.
Using G4 modules you can control lamps, motors, motor starters, etc., directly from the card. These modules switch AC/DC voltages up to 3A and can sense the presence of a
voltage.
G5 analog input modules (available from Grayhill) measure voltages, temperature, and current. RPBASIC reads these modules and returns a number from 0 to 255.
PWM is jumperable to one
of two on-card opto rack positions. PWM frequency is adjustable from 170 Hz to 43 KHz. The "PWM" statement sets a duty cycle with 0.39% resolution.
Keypad and Display Ports
The RPC-52
interfaces to either LCD character or graphics displays. Contrast adjustment is provided for LCD character displays. The card supports both line and point type drawing commands. RPBASIC accesses these displays
with the "DISPLAY" command. When RPBASIC detects a keypad press, it debounces and buffers the information then returns a corresponding number to the display .
Memory
The RAM and real time clock are
automatically battery backed. You can store process variables and/or data in up to 512K of RAM using "PEEK" and "POKE" commands. A 32K flash EPROM comes with the RPC-52. This is enough to hold
about 800 lines of code.
Serial Ports
Two serial ports are available. The programming port is RS-232 only. You can use this port during run time for any purpose needed by your
application. The second port is either RS-232, -422, or -485. The RPC-52 has screw terminals for connecting RS-422/485. A termination network is provided for RS-485 communication.
RPBASIC-52 buffers input and
output characters and controls the RS-485 port for transmission. RPBASIC-52 supports standard baud rates. CTS and RTS control lines for RS-232 are provided. User jumpers set a card's address or ID on a 485
network.
Other Features
A battery backed, real time clock is standard. RPBASIC-52 reads and sets the date and time using "DATE" and "TIME" commands.
A programmable
EEPROM saves 80 bytes of numeric data. Use this EEPROM to store process variables when the risk of battery backed RAM is not acceptable. RPC-52 configurations are also stored in this EEPROM. On power-up, digital
ports, baud rate, display, and memory configurations are set, speeding up the setup portion of your program.
A watchdog timer can reset the card should a program "crash." The timer is reset using the
"WDOG" command.
Technical Information
Processor:
80C552 running at 22.1184 MHz.
Memory Capacity:
RAM: 32K, 128K, or 512K, battery backed
Flash EPROM: 32K
Digital I/O:
24 lines from an 82C55. Eight are buffered for 200 mA output.
Power Requirements:
+5V at 90 mA, no modules or devices attached.
Environmental:
Temperature: 0C to + 70C
Mechanical:
Size: 7" x 4.5"
Mounting: 0.156" holes, 0.25" from edges
