Loading ...
Sorry, an error occurred while loading the content.

Re: [cosmacelf] Re: USB to serial

Expand Messages
  • William Donnelly
    I ve never even heard of MC Revision E boards. (I don t think) It would be nice if you formalized the website for that stuff so it was more easily
    Message 1 of 11 , Mar 21, 2013
    • 0 Attachment
      I've never even heard of MC "Revision E" boards. (I don't think)
      It would be nice if you 'formalized' the website for that stuff so it was more
      easily readable, and followable as to what's going on. Maybe even have an
      e-mail list or something so you can send out announcements to interested
      people and customers to keep them up to date so it doesn't get lost in the fog.

      – Bill

      On 3/21/2013 1:26 PM, Lee Hart wrote:
       
      {snip}

    • Lee Hart
      ... Hi Chuck, Thanks for such a concise and complete write-up! I ll put it on my Membership Card web page, if you don t mind. A couple more comments. Does your
      Message 2 of 11 , Mar 21, 2013
      • 0 Attachment
        Chuck Yakim the-eagle@... wrote:
        > Here is what I have been using to have the Membership Card connect to
        > my PC using the USB serial adapter.
        >
        > USB to Serial converter
        > http://www.amazon.com/TRENDnet-RS-232-Serial-Converter-TU-S9/dp/B0007T27H8/ref=sr_1_1?ie=UTF8&qid=1363859869&sr=8-1&keywords=trendnet+tu-s9+usb+to+serial+converter
        >
        > RS-232 to TTL adapter
        > http://www.amazon.com/MAX232-RS232-Converter-Adapter-Module/dp/B00BXCYAO6/ref=sr_1_6?s=electronics&ie=UTF8&qid=1363860220&sr=1-6&keywords=max232+rs232+to+ttl+converter
        >
        > These two items are plugged together, one end will have the USB
        > connector while the other end (Max232) has a 6 pin connector in which
        > I only use for 4 pins (Vcc, Gnd, TX, and Rx) that are connected to
        > the Membership Card's front panel as follows: Vcc to J1 pin 14, Gnd
        > to J1 Pin 1, RX to J1 Pin 12 (Q line) and TX to R13 Pin 2 (/EF4 input
        > line).
        >
        > Note: on the Revision "D" front panel the TX line of the
        > Max232 is then connected to the junction between the "A/B" jumper and
        > R14.
        >
        > Important note: When not using the serial communication, the TX
        > line from the Max232 has to be disconnected from the front panel in
        > order to return the IN (/EF4 line) button to be restored to its
        > normal operating condition.

        Hi Chuck,

        Thanks for such a concise and complete write-up! I'll put it on my
        Membership Card web page, if you don't mind. A couple more comments.

        Does your USB-to-serial converter output true RS-232 levels (+/-12v), or
        is it in fact TTL-level (0-5v) outputs? The ones I have are both the
        latter (despite advertising claims to the contrary).

        You can also wire your 0-5v TTL-level serial I/O to J2, the front panel
        25-pin D-connector. Q (serial RX) is on J2 pin 15, and /EF4 (TX) is on
        J2 pin 1. Ground is on J2 pins 19, 20, and 21.

        The Rev.E boards (which I am currently shipping) can directly accept
        RS-232 levels at J2 pin 1 because it has a 6.8k series resistor. This,
        plus the clamping diodes inside CMOS OR gate U8A allow +/-12v swings.
        The Rev.E board also can have VCC on J2 pin 18 via diode D12.

        Depending on how closely your device follows the RS-232 standard, you
        can send serial data and *power* the Membership Card entirely with the
        RS-232 interface. Connect J2 pin 18 to an RS-232 handshake line that is
        set to be always high. Try THAT with an Arduino! :-)
        --
        Any intelligent fool can make things bigger, more complex, and more
        violent. It takes a touch of genius, and a lot of courage, to move in
        the opposite direction. -- Albert Einstein
        --
        Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
      • the-eagle@att.net
        Thanks Lee for your response, The TRENDnet TU-S9 USB to RS-232 is a true RS-232 adapter, ...
        Message 3 of 11 , Mar 21, 2013
        • 0 Attachment
          Thanks Lee for your response, The TRENDnet TU-S9 USB to RS-232 is a true RS-232 adapter,
          > USB to Serial converter
          >
          http://www.amazon.com/TRENDnet-RS-232-Serial-Converter-TU-S9/dp/B0007T27H8/ref=sr_1_1?ie=UTF8&qid=1363859869&sr=8-1&keywords=trendnet+tu-s9+usb+to+serial+converter

          > RS-232 to TTL adapter
          >
          http://www.amazon.com/MAX232-RS232-Converter-Adapter-Module/dp/B00BXCYAO6/ref=sr_1_6?s=electronics&ie=UTF8&qid=1363860220&sr=1-6&keywords=max232+rs232+to+ttl+converter

          However the MAX232 on the receiving end (from your PC) "steals" and charges a capacitor to the +/-12 to +/-15 volts (from the received signal from the PC) to be used when transmitting the TTL to RS-232. From the input side of the MAX232 is all done with TTL logic voltages (0 thru 5 volts).

          About 8 or so months ago, I wrote a software UART program for the Membership Card that is independent of the clock speed of the Membership Card. I have had great success with this software between the Membership Card and the Hyperterminal that is included in Windows XP. Understanding that I do NOT have an assembler for the 1802, I did this the old fashion old, pencil and paper to chart the op codes and addresses out. The entire software to read or send a byte serially from the membership Card is under 256 bytes using the SCRT (standard Call and Return Technique) which was all new to me about a year ago. Back in 1978 when I started messing around with the 1802 I never heard of the SCRT stuff. My main goal doing this serial interface with the Membership Card was to somehow make Tiny Basic a reality in this day and age of the modern PC.

          Chuck Yakym


          --- In cosmacelf@yahoogroups.com, Lee Hart <leeahart@...> wrote:
          >
          > Chuck Yakim the-eagle@... wrote:
          > > Here is what I have been using to have the Membership Card connect to
          > > my PC using the USB serial adapter.
          > >
          > > USB to Serial converter
          > > http://www.amazon.com/TRENDnet-RS-232-Serial-Converter-TU-S9/dp/B0007T27H8/ref=sr_1_1?ie=UTF8&qid=1363859869&sr=8-1&keywords=trendnet+tu-s9+usb+to+serial+converter
          > >
          > > RS-232 to TTL adapter
          > > http://www.amazon.com/MAX232-RS232-Converter-Adapter-Module/dp/B00BXCYAO6/ref=sr_1_6?s=electronics&ie=UTF8&qid=1363860220&sr=1-6&keywords=max232+rs232+to+ttl+converter
          > >
          > > These two items are plugged together, one end will have the USB
          > > connector while the other end (Max232) has a 6 pin connector in which
          > > I only use for 4 pins (Vcc, Gnd, TX, and Rx) that are connected to
          > > the Membership Card's front panel as follows: Vcc to J1 pin 14, Gnd
          > > to J1 Pin 1, RX to J1 Pin 12 (Q line) and TX to R13 Pin 2 (/EF4 input
          > > line).
          > >
          > > Note: on the Revision "D" front panel the TX line of the
          > > Max232 is then connected to the junction between the "A/B" jumper and
          > > R14.
          > >
          > > Important note: When not using the serial communication, the TX
          > > line from the Max232 has to be disconnected from the front panel in
          > > order to return the IN (/EF4 line) button to be restored to its
          > > normal operating condition.
          >
          > Hi Chuck,
          >
          > Thanks for such a concise and complete write-up! I'll put it on my
          > Membership Card web page, if you don't mind. A couple more comments.
          >
          > Does your USB-to-serial converter output true RS-232 levels (+/-12v), or
          > is it in fact TTL-level (0-5v) outputs? The ones I have are both the
          > latter (despite advertising claims to the contrary).
          >
          > You can also wire your 0-5v TTL-level serial I/O to J2, the front panel
          > 25-pin D-connector. Q (serial RX) is on J2 pin 15, and /EF4 (TX) is on
          > J2 pin 1. Ground is on J2 pins 19, 20, and 21.
          >
          > The Rev.E boards (which I am currently shipping) can directly accept
          > RS-232 levels at J2 pin 1 because it has a 6.8k series resistor. This,
          > plus the clamping diodes inside CMOS OR gate U8A allow +/-12v swings.
          > The Rev.E board also can have VCC on J2 pin 18 via diode D12.
          >
          > Depending on how closely your device follows the RS-232 standard, you
          > can send serial data and *power* the Membership Card entirely with the
          > RS-232 interface. Connect J2 pin 18 to an RS-232 handshake line that is
          > set to be always high. Try THAT with an Arduino! :-)
          > --
          > Any intelligent fool can make things bigger, more complex, and more
          > violent. It takes a touch of genius, and a lot of courage, to move in
          > the opposite direction. -- Albert Einstein
          > --
          > Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
          >
        • Lee Hart
          ... Rev.E is barely different from Rev.D. Both can do the RS-232 and power via the 25-pin connector trick. The only notable change is that rev.E has room for a
          Message 4 of 11 , Mar 21, 2013
          • 0 Attachment
            On 3/21/2013 2:16 PM, William Donnelly wrote:
            >
            >
            > I've never even heard of MC "Revision E" boards. (I don't think)
            > It would be nice if you 'formalized' the website for that stuff so it
            > was more
            > easily readable, and followable as to what's going on. Maybe even have an
            > e-mail list or something so you can send out announcements to interested
            > people and customers to keep them up to date so it doesn't get lost in
            > the fog.

            Rev.E is barely different from Rev.D. Both can do the RS-232 and power
            via the 25-pin connector trick. The only notable change is that rev.E
            has room for a bigger supercapacitor at C5 (it was 0.022F, now 0.22F).

            You're right. I can add more of this to the website. It's in the manual,
            but you'd have to download it to read it.
            --
            The greatest pleasure in life is to create something that wasn't there
            before. -- Roy Spence
            --
            Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
          • the-eagle@att.net
            Lee, I understand that the RS-232 Space is a positive voltage (logical LO) while a Mark is a negative voltage (logical HI), while in digital logic a HI is a
            Message 5 of 11 , Mar 21, 2013
            • 0 Attachment
              Lee,
              I understand that the RS-232 Space is a positive voltage (logical LO) while a Mark is a negative voltage (logical HI), while in digital logic a HI is a positive voltage and a LO is at or near a ground. For the Max232 to be a true TTL converter, one does need to invert the the output. This is easy to do, either add an inverter to the output or one can change their software to match the standard TTL logic of a HI is a positive voltage and a LO is near or at ground. I decided to do it without the inverter, no added parts needed because it was all done with the software. With an inverter added, then there would be no need to open the MAX232 output from the /EF4 line on the front panel of the Membership Card (what a plus). By the Way; I have been looking over the schematic of the MC Auto Load Rev B schematic and have started to think about adding a RS-232 interface to it, matching the TTL logic (inversion). I'll keep ya posted.

              Chuck Yakym


              --- In cosmacelf@yahoogroups.com, Lee Hart <leeahart@...> wrote:
              >
              > On 3/21/2013 3:05 PM, the-eagle@... wrote:
              > > Thanks Lee for your response, The TRENDnet TU-S9 USB to RS-232 is a
              > > true RS-232 adapter,
              >
              > Ah; thanks! That is useful to know for other projects.
              >
              > But then, what are you using the RS-232 to serial converter for? You
              > shouldn't need it. The Membership Card can accept either TTL or RS-232
              > levels.
              >
              > The only difference is that the MAX232 also inverts the data. Your
              > software would need to take the inversion into account. In fact, if you
              > get it so the idle state for the receive line is high, then the IN
              > button on the Membership Card front panel still works even with the
              > serial connection (pressing it pulls the EF4 pin low).
              >
              > > About 8 or so months ago, I wrote a software UART program for the
              > > Membership Card that is independent of the clock speed of the
              > > Membership Card.
              >
              > That's a good classic program. There's another example in RCA's UT4
              > monitor ROM. I also have one in my Tiny BASIC and 8TH implementations.
              > They too were written the "hard way", with pencil and paper. :-)
              >
              > > My main goal doing this serial interface with the Membership Card
              > > was to somehow make Tiny Basic a reality in this day and age of
              > > the modern PC.
              >
              > Tom Pittman even wrote an Adventure game in Tiny BASIC. I ran it on the
              > Membership Card a while back. Man, that was a "blast from the past"!
              >
              > --
              > For every complex problem, there is a solution that is simple, obvious,
              > and wrong. -- H.L. Mencken
              > --
              > Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
              >
            • Lee Hart
              ... Ah; thanks! That is useful to know for other projects. But then, what are you using the RS-232 to serial converter for? You shouldn t need it. The
              Message 6 of 11 , Mar 21, 2013
              • 0 Attachment
                On 3/21/2013 3:05 PM, the-eagle@... wrote:
                > Thanks Lee for your response, The TRENDnet TU-S9 USB to RS-232 is a
                > true RS-232 adapter,

                Ah; thanks! That is useful to know for other projects.

                But then, what are you using the RS-232 to serial converter for? You
                shouldn't need it. The Membership Card can accept either TTL or RS-232
                levels.

                The only difference is that the MAX232 also inverts the data. Your
                software would need to take the inversion into account. In fact, if you
                get it so the idle state for the receive line is high, then the IN
                button on the Membership Card front panel still works even with the
                serial connection (pressing it pulls the EF4 pin low).

                > About 8 or so months ago, I wrote a software UART program for the
                > Membership Card that is independent of the clock speed of the
                > Membership Card.

                That's a good classic program. There's another example in RCA's UT4
                monitor ROM. I also have one in my Tiny BASIC and 8TH implementations.
                They too were written the "hard way", with pencil and paper. :-)

                > My main goal doing this serial interface with the Membership Card
                > was to somehow make Tiny Basic a reality in this day and age of
                > the modern PC.

                Tom Pittman even wrote an Adventure game in Tiny BASIC. I ran it on the
                Membership Card a while back. Man, that was a "blast from the past"!

                --
                For every complex problem, there is a solution that is simple, obvious,
                and wrong. -- H.L. Mencken
                --
                Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
              Your message has been successfully submitted and would be delivered to recipients shortly.