Rverter interface on Amazon

[Jeffrey Worley]

Here's a link to what I suspect will be a plug and play replacement for a homebuilt rverter.  I bought it already and will report.  My purpose is to provide an RS232 port for my 8-bit to put Cheez Daddy's House of Funk back online using telnet instead of Ma Bell.

 

https://www.amazon.com/MAX3232-Connector-Converter-Equipment-Upgrades/dp/B07PFB4MHR/ref=sr_1_5?keywords=max232&qid=1566430415&s=gateway&sr=8-5

 

** TNM **

[Kyle22]

You still need to use the Motor Control line to get it off of SIO when using other devices.

 

[Dropcheck]

I doubt this is a Rverter substitute.  Yes it does convert signals from the DB9 connector to serial TX/RX GND and power, but it does nothing with the control signal needed to fully use it with other Atari SIO devices on the bus.  You'll still need the first half of the Rverter circuit for that. 

 

Sorry if this is redundant. 

Edited August 22, 2019 by Dropcheck

[ricortes]

Probably not a huge deal, the MAX3232 being RS232 compatible will always have a built in resistance/load. The load will be significant compared to a real Atari device like a 1050, on the order of 3k-6k Ohms OR ttl load vs maybe 100k-200k. Nice find though  I remember when the MAX232 first came out the street price was something like $6/each. Nice to see the derivative with all the hardware is down to $1.80 a pop.

[Kyle22]

I do not believe that this particular part could be of use for us because it is Rx/Tx only. No control lines at all.

At least some versions of the R:Verter included a couple control signals. Not enough, I want to see proper RTS/CTS flow control. DTR would be nice as well.

I think thie R:Verter AND it's R: Handler can be improved upon. I like it because is allows POKEY to control the Baud rate. There is no speed limit.

 

[Jeffrey Worley]

Not to confuse the Rverter with an APE interface, but this ought to work.  The Rverter and its derivatives do not have flow control.  The P:R: Connection and the 850 and the ATR8000 do not have hardware flow control.  It is true that a Ring Indicate line might be handy for some functions, but so far as I recall, no bbs uses that.  The bbs programs use the AT command set and wait for a 'ring' string from a smartmodem to answer then by  sending the modem an "ATA".  THis is all software control.  XON/XOFF flow control is the only available on the Atari but for the MIO (With the extensions I've only heard of), and the CSS Black Box, which was the first interface and only in my hands-on experience, that had hardware flow control.  The Rverter works and plays well with other devices on the chain and I see no reason why this won't.  We don't use baudrates that generally require hardware flow control anyway.  Even at 9600 baud the Atari is pretty good at keeping up.  We aren't running a drive on this, just a modem.  I intend to use it to run the Lantronix interface I have in the mail and put my board back up.  Seriously, the single-chip Rverter/SIO2PC interface uses a single 1489.  Can't get much bare-er than that.

 

Best,

 

Jeff

[Dropcheck]

2 hours ago, Technoid Mutant said:

Not to confuse the Rverter with an APE interface, but this ought to work.  The Rverter and its derivatives do not have flow control.  The P:R: Connection and the 850 and the ATR8000 do not have hardware flow control.  It is true that a Ring Indicate line might be handy for some functions, but so far as I recall, no bbs uses that.  The bbs programs use the AT command set and wait for a 'ring' string from a smartmodem to answer then by  sending the modem an "ATA".  THis is all software control.  XON/XOFF flow control is the only available on the Atari but for the MIO (With the extensions I've only heard of), and the CSS Black Box, which was the first interface and only in my hands-on experience, that had hardware flow control.  The Rverter works and plays well with other devices on the chain and I see no reason why this won't.  We don't use baudrates that generally require hardware flow control anyway.  Even at 9600 baud the Atari is pretty good at keeping up.  We aren't running a drive on this, just a modem.  I intend to use it to run the Lantronix interface I have in the mail and put my board back up.  Seriously, the single-chip Rverter/SIO2PC interface uses a single 1489.  Can't get much bare-er than that.

 

Best,

 

Jeff

I think you're confusing flow control with SIO bus contention. ?  What we've been saying is that the motor control signal gives the normal Rverter I/II circuit the ability to reside on the SIO bus without interfering with other SIO devices.  This MAX232 converter simply converts the RS232 signals to a serial RX/TX/GND/VCC signal output.   It may very well work, if it's the only SIO device on the bus, but lacks the ability to co-exist with other devices without a on/off switch.  It is not a complete Rverter I/II substitute. 

[Jeffrey Worley]

2 minutes ago, Dropcheck said:

I think you're confusing flow control with SIO bus contention. ?  What we've been saying is that the motor control signal gives the normal Rverter I/II circuit the ability to reside on the SIO bus without interfering with other SIO devices.  This MAX232 converter simply converts the RS232 signals to a serial RX/TX/GND/VCC signal output.   It may very well work, if it's the only SIO device on the bus, but lacks the ability to co-exist with other devices without a on/off switch.  It is not a complete Rverter I/II substitute. 

Ah, ok.  That makes good sense.  I don't have a control line on this, but I plan to use it with non-sio devices for mass-storage, so for a buck it looks good.  I still haven't tried it though.  I got sidetracked with my friend's U1MB since the Xilinx programmer came today.  Everything is up-to-date now.  Wow, that was something of a mission.  The wireing to the U1MB worked the first time, but getting my Dupont connectors onto that itty bitty connector on the U1MB took some doing.

 

** TNM **

[Jeffrey Worley]

The Rverter works.  I hung it off of a spare xl this evening.  Here's some photos of me typing to myself through it in Bobterm.  The text is being sent out of the rverter and then back in via the orange loopback wire.  The typo is just that, not a receive error.

 

Here's some pics.

 

** TNM **

[Dropcheck]

Great!  ?

 

Like I said it is possible for this to work as a simple converter between basic RS232 signals and something the Atari can understand.  The big test is what do you need to connect to a real BBS and will it work unaltered with other SIO devices on the bus as well.  That's where you may run into problems. 

[ricortes]

6 hours ago, Dropcheck said:

Great!  ?

 

Like I said it is possible for this to work as a simple converter between basic RS232 signals and something the Atari can understand.  The big test is what do you need to connect to a real BBS and will it work unaltered with other SIO devices on the bus as well.  That's where you may run into problems. 

IDK, I can understand not being a fan of hot plugging stuff, it's just that we have progressed so far it is possible to have a system that doesn't use SIO for anything other then an RS232 device. It would be pretty simple to add the circuitry to isolate the device so it wouldn't be sending garbage out when you accessed a 1050 or ??? on SIO bus. Simple double throw switch if you could accept doing it manually or tristate buffer like a 74ls245 if you wanted to make it compatible. It would add to the complexity of course but maybe $.40? Probably easier/cheaper ways to do it then that like using the command line on half of a NOR/NAND gate or sumtin. That's what the Sider's did https://www.google.com/url?sa=i&source=images&cd=&cad=rja&uact=8&ved=2ahUKEwiOkYeShKHkAhVdHzQIHWO2DCcQjRx6BAgBEAQ&url=https%3A%2F%2Fatariage.com%2Fforums%2Ftopic%2F284097-mss-100rverter-connection-help%2F&psig=AOvVaw2M2AKeH2LyfMtLzbUJ-Lx6&ust=1566925873484199

[Kyle22]

Yes, you MUST get it OFF of SIO during other device access. Motor control could also be tied to CTS to stop the other end from sending while SIO is busy.

 

Edit: Actually, it would be motor with a delay circuit, and a mod in the R: Handler's routine to add buffer.

 

Edited August 27, 2019 by Kyle22

[Jeffrey Worley]

Well, the interface is plenty fast and works quite well.  I suspected it would spew garbage out of it's port when the sio was active doing anything else, like reading from an sio disk drive, so no surprises there.  I'm using a Side2 cart for mass storage, so the sio is free to be an rs232 without contention.  I went ahead and installed it internally.  Here's some pics.  Just drilled a couple of holes and used the file on my Leatherman to get it to the right dimensions.  The only time it makes noise on the sio bus is when it is receiving data, which I can't prevent, so it will step all over any sio going on, wrecking frames left and right, but no black smoke.  If the RS232 is quiet, or if it is disconnected, the sio works just peachy for other drives.  Manual handler  -- level eight networking.

 

 

 

For what was it?  a buck fifty?  A buck eighty?  I got a nice internal serial port.

 

 

 

 

 

[_The Doctor__]

It could have just remained as an inline cable really...

[Jeffrey Worley]

1 minute ago, _The Doctor__ said:

It could have just remained as an inline cable really...

I have no sio connectors, only two sio cables and one is already hosting an sio2usb.  ?

 

** TNM **

[Kyle22]

6 minutes ago, Technoid Mutant said:

I have no sio connectors, only two sio cables and one is already hosting an sio2usb.  ?

 

** TNM **

I am guessing that you mean SIO2PC, USB version, such as Lotharek's lovely device.

 

[Kyle22]

If that is the case, please make sure you are NOT using a BT or NON /COMMAND line protocol in RespeQt. Unpredictable things may happen to mounted drives when doing RS-232 this way.

An emulated drive can FORMAT a disk easily if triggered by sequences of characters over SIO.

 

This is dangerous territory.

It is always best to gate it off of the SIO bus when other devices are used. This is done using the /Motor Control line.

 

 

[Jeffrey Worley]

8 hours ago, Kyle22 said:

I am guessing that you mean SIO2PC, USB version, such as Lotharek's lovely device.

 

Yep.  I used a usb to serial breakout board and wired it onto one sio connector on one of my two sio cables.  This way the cable is still completely useable as an sio cable, but adds the functionality of an Sio2usb.  It is what I used to see what kind of garbage I got on the rverter when I access drives on the sio chain.

 

I use 'Atarisio' under Linux for my sio drive emulation.  It works very well, better than RespeQt or AspeQt, especially with regard to low pokey divisors (like zero, or two :-)))  The only thing I wish I had was an emulator that would mount the native PC filesystem as an emulated Spartados disk so I could just copy files from the pc to Atari partitions on the 8-bit.  Else, to move large amounts of data I have to yank the SD card from the Side2 and copy the files to it and mule it back to the Atari.  More level eight networking.

 

** TNM **

 

 

[_The Doctor__]

PCLINK at divisor zero works for most of us with Respeqt... An APE's PCMIRROR, or APELOADER like working at divisor zero as well.

 

Depends on your Peripheral emulator, OS, Patch, DOS and what each of their filters are capable of.

[Faicuai]

3 hours ago, Technoid Mutant said:

Yep.  I used a usb to serial breakout board and wired it onto one sio connector on one of my two sio cables.  This way the cable is still completely useable as an sio cable, but adds the functionality of an Sio2usb.  It is what I used to see what kind of garbage I got on the rverter when I access drives on the sio chain.

 

I use 'Atarisio' under Linux for my sio drive emulation.  It works very well, better than RespeQt or AspeQt, especially with regard to low pokey divisors (like zero, or two :-)))  The only thing I wish I had was an emulator that would mount the native PC filesystem as an emulated Spartados disk so I could just copy files from the pc to Atari partitions on the 8-bit.  Else, to move large amounts of data I have to yank the SD card from the Side2 and copy the files to it and mule it back to the Atari.  More level eight networking.

 

** TNM **

 

 

 

FYI, that's already known-and-done.

 

Already exists, and it is a combined functionality of SpartaDOS-X (PCLINK.SYS), plus High-Speed SIO drivers (preferably at BIOS level, supporting PCLINK) plus SIO-peripheral emulator (which also must support PCLINK). If the chain is complete, just mount PC file-system folder in SIO-emulator, and that's it.

 

In the event that "AtariSIO" does not provide PCLINK support, then that is a big no-no, which automatically puts it quite behind RespeQt or any other SIO-emulator that does supports it.

 

As Doc mentioned, Pokey divisor 0 (zero) is a day-in/day-out walk-in-the-park under SDX / RespeQt (+PCLink), and even on stock HW (no SIO-related modifications). 10-to-12 KBytes/sec of throughput, virtually guaranteed.

Edited August 29, 2019 by Faicuai

[Faicuai]

12 hours ago, Kyle22 said:

If that is the case, please make sure you are NOT using a BT or NON /COMMAND line protocol in RespeQt. Unpredictable things may happen to mounted drives when doing RS-232 this way.

An emulated drive can FORMAT a disk easily if triggered by sequences of characters over SIO.

 

This is dangerous territory.

It is always best to gate it off of the SIO bus when other devices are used. This is done using the /Motor Control line.

 

 

Dead-on!