G228 REV F SCHEMATIC REV H PCB INHIBIT DRIVER (2 7440) Manual test, using Oscilloscope to check logic NOTES 7440 outputs (active low) are not at connector (drive tranformers) but can be 'clipped' at the 330 ohm pullup (to +5V) resistors that connect thru the transformers to 7440 outputs output 00 is at the top (pin A is top) output 01 is next output 10 is next output 11 is at the bottom (pin V is bottom) actual outputs are pulses due to transformer coupling. Must scope them. Note: "P" for PULLUP OUTPUTS on the open collector outputs; Emitters are driven low. output pulses low (0.?? v) when active. pulse width is ???? when active TODO: still need a way to test diodes, output transformers PINS 1 I AA1 ENABLE (NANDed into OUTPUT 00, OUTPUT 01, OUTPUT 10, OUTPUT 11) 2 I AE2 ENABLE 0/1 (NANDed into OUTPUT 00, OUTPUT 01) 3 I AN2 ENABLE 2/3 (NANDed into OUTPUT 10, OUTPUT 11) 4 I AD2 BIT 00 NAND (ENABLE, ENABLE 0/1, BIT 00) is OUTPUT 00 5 I AD1 BIT 01 NAND (ENABLE, ENABLE 0/1, BIT 01) is OUTPUT 01 6 I AM2 BIT 10 NAND (ENABLE, ENABLE 2/3, BIT 10) is OUTPUT 10 7 I AL1 BIT 11 NAND (ENABLE, ENABLE 2/3, BIT 11) is OUTPUT 11 8 P AL2 OUTPUT 00 COLLECTOR (PULLUP SO CAN SCOPE OUTPUT) 9 P AK1 OUTPUT 01 COLLECTOR (PULLUP SO CAN SCOPE OUTPUT) 10 P AU2 OUTPUT 10 COLLECTOR (PULLUP SO CAN SCOPE OUTPUT) 11 P AS1 OUTPUT 11 COLLECTOR (PULLUP SO CAN SCOPE OUTPUT) 12 I AF2 OUTPUT 00 EMITTER (ALWAYS GROUNDED) 13 I AE1 OUTPUT 01 EMITTER (ALWAYS GROUNDED) 14 I AP2 OUTPUT 10 EMITTER (ALWAYS GROUNDED) 15 I AM1 OUTPUT 11 EMITTER (ALWAYS GROUNDED) IIIIIIIPPPPIIII ; all 128 patterns. (each output is ON for 32 pulses) 000000011110000 00000011111 00000101111 00000111111 00001001111 00001011111 00001101111 00001111111 00010001111 00010011111 00010101111 00010111111 00011001111 00011011111 00011101111 00011111111 00100001111 00100011111 00100101111 00100111111 00101001111 00101011111 00101101111 00101111111 00110001111 00110011111 00110101111 00110111111 00111001111 00111011111 00111101111 00111111111 01000001111 01000011111 01000101111 01000111111 01001001111 01001011111 01001101111 01001111111 01010001111 01010011111 01010101111 01010111111 01011001111 01011011111 01011101111 01011111111 01100001111 01100011111 01100101111 01100111111 01101001111 01101011111 01101101111 01101111111 01110001111 01110011111 01110101111 01110111111 01111001111 01111011111 01111101111 01111111111 10000001111 10000011111 10000101111 10000111111 10001001111 10001011111 10001101111 10001111111 10010001111 10010011111 10010101111 10010111111 10011001111 10011011111 10011101111 10011111111 10100001111 1010001111X 101001011X1 101001111XX 10101001X11 10101011X1X 10101101XX1 10101111XXX 1011000X111 1011001X11X 1011010X1X1 1011011X1XX 1011100XX11 1011101XX1X 1011110XXX1 1011111XXXX 11000001111 1100001111X 110001011X1 110001111XX 11001001X11 11001011X1X 11001101XX1 11001111XXX 1101000X111 1101001X11X 1101010X1X1 1101011X1XX 1101100XX11 1101101XX1X 1101110XXX1 1101111XXXX 11100001111 1110001111X 111001011X1 111001111XX 11101001X11 11101011X1X 11101101XX1 11101111XXX 1111000X111 1111001X11X 1111010X1X1 1111011X1XX 1111100XX11 1111101XX1X 1111110XXX1 1111111XXXX END