Opto22 LC2

0108 Optomux and Local Controller Programming Notes
   Apps and programs for LC2 / LC4 controllers in IBM PC BASIC or FORTH 83.
0173 LC2/LC4 Opto 22 FORTH (subset of FORTH-83)
0201 LC2/LC4 BASIC Details

LC2 Single-board Controller LC2 (115v), LC2A(220v), LC2DC (10-28v DC) - Lacks Pamux hardware.
   Z80B 8-bit CPU, 4.9 MHz, 32KB EPROM, 32KB RAM

Configuring the Host and Applying Power to LC2

After connecting the LC2 to the Host, configure and initialize the host's serial port with the following parameters:

BAUD RATE: 300, 1200, 2400 4800, 9600, 19200 or 38400

If you are using an IBM Personal Computer or compatible as a host, the utility LCTERM simulates a terminal with upload and download capabilities. The documentation (what little there is) is in LCTERM.TXT.

After the host is configured, apply power to LC2. If everything is working correctly, a sign on message should appear at the host. If this message does not appear, make sure the "AUTO" jumper is NOT installed. If it is installed, turn power off on LC2, remove the jumper, and turn power back on. If you still do not get any response, check the LED indicator "TH" to be sure it flashes briefly when power is applied. This LED indicates that LC4 is transmitting to the host (try a slower baud rate to make it easier to view the flashing LED). Double check the wiring, LC2 configuration, and host configuration to make sure there are no errors.

LCterm Terminal emulation program used with LC2. Files can be down-loaded and up-loaded between LC2 and the IBM PC.
LCterm Help File  Word *.DOC format.

LC2 Newer version, 1992. 005019B [P]

AUTO Boot Jumper 9
Battery BR-2/3A, 3v
GROUP A Term and Bias
J1 RS-422/485 DE9
Optomux LEDs FO, TO, FH, TH
TVS P6KE 6V8 CA (8x)
U2,3 TI 75174N
U4 M27C256B-20F1
U5 HM62256BLP-7
U9 SGS Z8400BB1 Z80B CPU
U10 SGS Z8470BB1 Z80B DART
U13 RTC72421
U14 SN74LS32N Quad 2-Input OR
U15 4.9152 MHz osc
U18 74HCT4040N Binary Counter
U20 DS1232L
U21 74HCT20N Dual 4-Input NAND

AUTO jumper runs to Z80B DART Pin 10, Wait/ReadyA, W/RDYA (inverse)

DS1232 MicroMonitor Datasheet (Power supply, software execution, and external override)
   DS1232L Pin 1 Pushbutton Reset Input, PBRST (inverse) connects to Z80B CPU Pin 25, RESET (inverse)
   DS1232L Pin 7 Strobe Input, ST (inverse) connects to Z80B DART Pin 16 DTRA (inverse)
HM62256B 32Kx8 SRAM Datasheet
RTC-72421 4-bit Real Time Clock Module Datasheet
Transil P6KE 6V8 CA Transient Voltage Surge Suppressor (Bi-Directional) Datasheet
   Note: Bi-directional devices are not marked with a Cathode band!
Z80BCPU (Z8400BB1) CPU Datasheet
Z80BDART (Z8470BB1) Dual Asynchronous Receiver/Transmitter Datasheet
SN75174N Quadruple Differential Line Driver Datasheet
M27C256B 32Kx8 UV EPROM Datasheet


Set the Baud rate for communicating with Host (H) and Optomux (O) network.
Host can be a PC or another Optomux device upstream.
Optomux is for downstream connection with an Optomux device.

300 (Modem or Radio Link)
1200 (Modem or Radio Link)
9600 (Default)

Group A Jumpers
Provides termination and bias resistor connections for the RS-422/485 port.
Note: I do not have an LC2 hardware guide. This is a guess, but the traces do run from J1 to the screw terminals to the Group A Jumpers.

Maximum RS-422/485 Serial Speeds for Both Optomux (O) and Host (H)

Old, 4 CMOS RAM chips - 19.2Kb circa 1987
New, 1 CMOS RAM chip, - 38.4Kb circa 1992

Old - 4x HM6264A Series 8Kx8 SRAM, 32K total
New - 1x HY62256ALP-100 32Kx8 SRAM

Old - Watchdog crystal - 32kHz feeds U13 - looks like an NS watchdog IC.

New DE9 RS-422 Port

0466 AC7 RS232 to RS422 Converter (AC7 is 12v DC)
0233 AC7A - AC7B Users Guide RS232-RS422/485 Converter (AC7A is 120v, AC7B is 220v)
0960 AC7A/B Adapter Card Data Sheet  RS232-RS422/485 Converter (AC7A is 120v, AC7B is 220v)

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Louis F. Ohland, Peter H. Wendt, David L. Beem, William R. Walsh, Tatsuo Sunagawa, Tomáš Slavotínek, Jim Shorney, Tim N. Clarke, Kevin Bowling, and many others.

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