I use Br@y's terminal if I need more special analysis than just seeing ASCII-characters
Bray's terminal can dipslay the received bytes as ASCII, binary, decimal, and hex at the same time
it has a log function
and even has a script-function
RS232 considers any voltages at or below -3V as high (1) and voltages at or below +3V as low (0).
That is blindly quoting the "standard" which is anything but and does not reflect industry use over the last few decades. All RS-232 chips exhibit about the same switching characteristics as a resistive input into a Prop pin.
Let's see, which should we choose, 2 resistors, or the magic chip and capacitors. That decision should be a no-brainer surely, we shouldn't be having this discussion when we are technical enough to discern the true nature of the beast.
That is blindly quoting the "standard" which is anything but and does not reflect industry use over the last few decades. All RS-232 chips exhibit about the same switching characteristics as a resistive input into a Prop pin.
Let's see, which should we choose, 2 resistors, or the magic chip and capacitors. That decision should be a no-brainer surely, we shouldn't be having this discussion when we are technical enough to discern the true nature of the beast.
I understand what you are saying..
But realize that this is my first hardware level project besides simple stuff. 90% of my days is writing business application logic, so I am sorry if I am a little cautious as I tread into unknown waters..
I understand what you are saying..
But realize that this is my first hardware level project besides simple stuff. 90% of my days is writing business application logic, so I am sorry if I am a little cautious as I tread into unknown waters..
Sure, but since I design data-communications hardware amongst other things for decades I'm speaking from a point of authority of this matter. My frustration is with the flimsy implementation of the standard because even with the flimsy implementation "it works" (and it does). Now by flimsy I'm not talking about the resistors, I'm talking about the chips that designers feel that they need, and there is nothing wrong with them, it's just that you can accomplish the same thing in a far simpler manner. Look, many decades ago they had receive chips that would only work according to the old "standards" in that they would require at least -3V to output a high but nobody wanted them because they were too picky and some devices failed to drive these receivers. Now the newer chips in the last few decades only need less than +1.3V or so for their output to go high and +1.45V to go low and that is NOT the standard. However the transmitter still happily obliges the standard with +/- transmit levels although as drive levels go they tend to be a poor cousin of the real standard.
So what I am saying is that you will not be at a disadvantage at all by using the two resistors but in fact it is far more rugged than the chip. Given two equally matched solutions, the simpler is the best.
Zetsu, if that data was displayed on a VT-100 as you mentioned in one of your posts it definitely has a start bit and at least one or perhaps two stop bits. It may have less than 8 data bits and perhaps a parity bit as well. Having 2 stop bits will not be a problem but having less than 8 data bits or a parity bit will cause some difficulty. One of your IT guys (probably one of the older ones) might be able to look at the VT-100 and determine the settings. If not, a bit of detective work will find them.
Comments
Bray's terminal can dipslay the received bytes as ASCII, binary, decimal, and hex at the same time
it has a log function
and even has a script-function
can be downloaded here
https://sites.google.com/site/terminalbpp/
or from the attachment
best regards
Stefan
That is blindly quoting the "standard" which is anything but and does not reflect industry use over the last few decades. All RS-232 chips exhibit about the same switching characteristics as a resistive input into a Prop pin.
Let's see, which should we choose, 2 resistors, or the magic chip and capacitors. That decision should be a no-brainer surely, we shouldn't be having this discussion when we are technical enough to discern the true nature of the beast.
I understand what you are saying..
But realize that this is my first hardware level project besides simple stuff. 90% of my days is writing business application logic, so I am sorry if I am a little cautious as I tread into unknown waters..
Sure, but since I design data-communications hardware amongst other things for decades I'm speaking from a point of authority of this matter. My frustration is with the flimsy implementation of the standard because even with the flimsy implementation "it works" (and it does). Now by flimsy I'm not talking about the resistors, I'm talking about the chips that designers feel that they need, and there is nothing wrong with them, it's just that you can accomplish the same thing in a far simpler manner. Look, many decades ago they had receive chips that would only work according to the old "standards" in that they would require at least -3V to output a high but nobody wanted them because they were too picky and some devices failed to drive these receivers. Now the newer chips in the last few decades only need less than +1.3V or so for their output to go high and +1.45V to go low and that is NOT the standard. However the transmitter still happily obliges the standard with +/- transmit levels although as drive levels go they tend to be a poor cousin of the real standard.
So what I am saying is that you will not be at a disadvantage at all by using the two resistors but in fact it is far more rugged than the chip. Given two equally matched solutions, the simpler is the best.
http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/SerialtoPropeller.pdf
Since I don't program through this port, I have the RES circuit removed. Works like a charm