DECISION COMPUTER INTERNATIONAL CO., LTD.
MULTI 8255/8253 CARD
Card Type | Data acquisition |
Chip Set | NEC 8253, 8255 |
I/O Options | Digital I/O ports (4), counter port |
Data Bus | 8-bit ISA |

CONNECTIONS | |||
Function | Label | Function | Label |
Digital I/O port 1 (see pinout below) | CN1 | 8255 chip for port 4 (channel 7) | U3 |
Digital I/O port 2 (see pinout below) | CN2 | 8255 chip for port 4 (channel 8) | U4 |
Digital I/O port 3 (see pinout below) | CN3 | 8255 chip for port 1 (channel 1) | U6 |
Digital I/O port 4 (see pinout below) | CN4 | 8255 chip for port 1 (channel 2) | U7 |
8253 counter port (see pinout below) | CN5 | 8255 chip for port 2 (channel 3) | U8 |
8255 chip for port 3 (channel 5) | U1 | 8255 chip for port 2 (channel 4) | U9 |
8255 chip for port 3 (channel 6) | U2 | ||
CN1-CN4 PINOUT | |||
Function | Pin | Function | Pin |
Channel 1A bit 0 | 1 | Channel 1C bit 2 | 19 |
Channel 1A bit 1 | 2 | Channel 1C bit 3 | 20 |
Channel 1A bit 2 | 3 | Channel 1C bit 4 | 21 |
Channel 1A bit 3 | 4 | Channel 1C bit 5 | 22 |
Channel 1A bit 4 | 5 | Channel 1C bit 6 | 23 |
Channel 1A bit 5 | 6 | Channel 1C bit 7 | 24 |
Channel 1A bit 6 | 7 | Ground | 25 |
Channel 1A bit 7 | 8 | Ground | 26 |
Channel 1B bit 0 | 9 | Channel 2A bit 0 | 27 |
Channel 1B bit 1 | 10 | Channel 2A bit 1 | 28 |
Channel 1B bit 2 | 11 | Channel 2A bit 2 | 29 |
Channel 1B bit 3 | 12 | Channel 2A bit 3 | 30 |
Channel 1B bit 4 | 13 | Channel 2A bit 4 | 31 |
Channel 1B bit 5 | 14 | Channel 2A bit 5 | 32 |
Channel 1B bit 6 | 15 | Channel 2A bit 6 | 33 |
Channel 1B bit 7 | 16 | Channel 2A bit 7 | 34 |
Channel 1C bit 0 | 17 | Channel 2B bit 0 | 35 |
Channel 1C bit 1 | 18 | Channel 2B bit 1 | 36 |
CN1-CN4 PINOUT (CON’T) | |||
Function | Pin | Function | Pin |
Channel 2B bit 2 | 37 | Channel 2C bit 1 | 44 |
Channel 2B bit 3 | 38 | Channel 2C bit 2 | 45 |
Channel 2B bit 4 | 39 | Channel 2C bit 3 | 46 |
Channel 2B bit 5 | 40 | Channel 2C bit 4 | 47 |
Channel 2B bit 6 | 41 | Channel 2C bit 5 | 48 |
Channel 2B bit 7 | 42 | Channel 2C bit 6 | 49 |
Channel 2C bit 0 | 43 | Channel 2C bit 7 | 50 |
Note:CN2 through CN4 are wired identically to CN1. CN1 has the signals for channels 1 and 2. CN2 through CN4 have the signals for channels 3 through 8, respectively. | |||
CN5 PINOUT | |||
Function | Pin | Function | Pin |
Ground | 1 | Counter 2B clock signal in | 18 |
Counter 1A clock signal in | 2 | Gate 2B signal | 19 |
Gate 1A signal | 3 | Counter 2B clock signal out | 20 |
Counter 1A clock signal out | 4 | Ground | 21 |
Ground | 5 | Counter 2C clock signal in | 22 |
Counter 1B clock signal in | 6 | Gate 2C signal | 23 |
Gate 1B signal | 7 | Counter 2C clock signal out | 24 |
Counter 1B clock signal out | 8 | Ground | 25 |
Ground | 9 | +5V DC power | 26 |
Counter 1C clock signal in | 10 | Ground | 27 |
Gate 1C signal | 11 | -5V DC power | 28 |
Counter 1C clock signal out | 12 | Ground | 29 |
Ground | 13 | +12V DC power | 30 |
Counter 2A clock signal in | 14 | Ground | 31 |
Gate 2A signal | 15 | -12V DC power | 32 |
Counter 2A clock signal out | 16 | Ground | 33 |
Ground | 17 | Ground | 34 |
USER CONFIGURABLE SETTINGS | |||
Setting | Label | Position | |
| » | Counter 1A uses internal clock source | JP1/A | Closed |
Counter 1A uses external clock source | JP1/A | Open | |
| » | Counter 1B uses internal clock source | JP1/B | Closed |
Counter 1B uses external clock source | JP1/B | Open | |
| » | Counter 1C uses internal clock source | JP1/C | Closed |
Counter 1C uses external clock source | JP1/C | Open | |
| » | Counter 2A uses internal clock source | JP2/A | Closed |
Counter 2A uses external clock source | JP2/A | Open | |
| » | Counter 2B uses internal clock source | JP2/B | Closed |
Counter 2B uses external clock source | JP2/B | Open | |
| » | Counter 2C uses internal clock source | JP2/C | Closed |
Counter 2C uses external clock source | JP2/C | Open | |
| » | Base I/O address set to 140h | JP3 | Closed |
Base I/O address set to 100h | JP3 | Open | |