Input 1
Input 2
Input 3
Input 4
Input 5
Input 6
Input 7
Input 8
Ground
When resistor network RN2 is installed, all inputs are pulled high
(on) and can be turned off by connecting a wire to the ground line.
J1-J4 - Address Select. These jumpers de-
fine the device number of the 8SC, allow-
ing 16 devices to coexist on a single serial
line. See "NCD-110 Addressing" for details.
J6 - Reserved for future expansion.
Jumper between the left two posts.
J5 - Baud Rate Select. In-
stall this jumper for 1200
baud operation; remove for
9600 baud operation.
To NCD-RSB Input
To NCD-RSB Output
To NCD-RSB Ground
To V+ (9 to 12 Volts)
To Power Supply Ground
Make sure you NEVER connect the power supply to this device backwards. Doing so will
destroy the 78L05 and possibly the PIC. Remember, minimal operation voltage is around 7
volts. Also, verify part orientation before proceeding. Watch for shorted solder connec-
tions. Please verify component placement before you continue.
When data is received by the computer from the 8SC, each pin that is connected to ground will return a unique
number. Example:
When no inputs are tied to ground, RN2 pulls all inputs high. This returns a 255.
When input 1 is the only line connected to ground, a 254 will be returned (255-1, 1 is the weight of input 1).
When input 4 is the only line connected to ground, a 247 will be returned (255-8, 8 is the weight of input 4).
When input 8 is the only line connected to ground, a 127 will be returned (255-128, 128 is the weight of input 8).
When inputs 1 and 4 are connected to ground, a 246 will be returned (1+8 weighted total is 9, so 255-9).
Input 1 is weighted by 1.
Input 2 is weighted by 2.
Input 3 is weighted by 4.
Input 4 is weighted by 8.
Input 5 is weighted by 16.
Input 6 is weighted by 32.
Input 7 is weighted by 64.
Input 8 is weighted by 128.
See the included program "8SCTESTB.BAS" for an example
of how to software decode the incoming number to the original
lines that were turned on or off. Also, many programs have
been included to decode the 8SC inputs to several desirable
output types. The method shown is the default method.
