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    8085 Assembler, adding another menu choice disables char input from sid (Resolved)?

    Hi, This program works fine as shown in the TeraTerm picture below the code. Working Code # ORG 00A3H # DB...
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    RS232 Framing Errors (Resolved)

    Hi, I started reading about parity, flow control and all that jazz, but I am clued out as to how to deal with dropped/corrupt serial frames. The articles say that checking parity doesn't 100% solve all the problems. I am currently using 9600, n , 8, 2. My program uses asynchronous serial...
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    8085 Assembly Language RIM Command Help Needed (Resolved)

    Hi, I was trying to remove the "spaghetti" from my spaghetti code and now it doesn't work. It displays the banner and then some junk characters in teraterm and doesn't wait for user input: Non-working code: ;8085 Monitor LXI SP,7FFFH JMP START # ORG 0006H ; Banner # DB DATA:20H,0DH,0AH,57H...
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    When to use Pull-Up Resistors on read/write pins of Memory connected to the 8085

    Hi, I noticed that 4.7k ohm pull-up resistors are used in this circuit on the read/write memory pins: Saundby's MAG 85(scroll down to yellow text), but in other circuits where the read/write / io/m signals are decoded by the 74138 for example, pull-ups are not used? Is it because in the MAG 85...
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    8085 Address Decoding

    Hi, I think that this looks correct, please confirm. I am ONLY showing my connection to the 62256 32k x 8 ram CE pin that I added to the web page picture, slide 15: When A13,A14,A15 are all low, the 2764 should be selected. When A15 is high, the 62256 should be selected. Keiichicom
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    8085 SOD Light a LED Assembly Language Code Question (Resolved)

    Hi, When I load this code into ROM and execute it on my 8085 based computer, it works fine. The LED connected to the SOD (serial output) lights and goes out: START: MVI A,C0 ; light the LED SIM MVI B,FF ; load the delay count into the B register DELAY: DCR B JNZ DELAY...
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    How do I eliminate noise in an 8085 circuit?

    Hi, I am still relatively new to microprocessor circuits. Please tell me how I can reduce or eliminate the noise introduced into the circuit below? I have a half-decent power supply with a stable output voltage(input about 12 volts, output about 5 volts): But there is noise in the...
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    How do I connect multiple 8255s to an 8085?

    Hi, I am ok on connecting one 8255 i/o chip to an 8085 mpu with an 74138 3 to 8 decoder chip but I am fuzzy on how to connect multiple 8255s? Can somebody please enlighten me, thanks?