The code requires a <space> key to be pressed to synchronise to the keyboard speed. Until that happens all keyodes are stripped. Resynchronisation occurs each time a keycode with the LSB (bit 0) = 1 is received.
Currently there is no buffering as I am going to fit the buffers into the cog so that it will work with SphinxOS.
Anyone wishing to test this can do so with no hardware changes to an existing keyboard circuit. This code totally ignores the keyboard clock pin, so only the keyboard data pin is used and utilises the exact same keyboard circuit (10K pullup and 100R series on the keyboard data pin, and a 10K pullup on the keyboard clock pin).
Note: bst is not required for compiling.
Postedit: v116 (code tidyup - no new features)
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Links to other interesting threads:
If you gone do one pin, do it the smart way by using a programmable ic. ·
You can have one pin for both keyboard and mouse. ·
This 50cents·pdip-8, have 4 inputs/outputs
So 2 pins for keyboard and 2 for mouse. ·
It also have on fixed output, this is the one you use as one wire serial to the prop.
Some custom·Tx UART or·Manchester·will do. · http://www.mouser.com/ProductDetail/Freescale-Semiconductor/MC9RS08KA1CPC/?qs=N2XN0KY4UWUndDgeHLAsxA%3d%3d ·
I'm up for the task of programming 25 units when I have the time.
It is currently in the form of a standalone test program which requires the serial pc connection to display the keystrokes and a PS2 keyboard connected to P26/P27 although P27 is not used.
The buffer is internal to the cog and it is ready to add into SphinxOS.
Please report any problems. Can be compiled with PropTool.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Links to other interesting threads:
I used an old computer CD cable. I cut the extra mounting clips off the 4-pin plug. My 4-pin plug had another set of finer cables connected to another smaller plug. I carefully cut those wires off.
A: The white wire has 100R soldered with yellow heatshrink covering the joint. The other end of the 100R is soldered to a 10K. A 10K is also soldered to the PS2 socket (clock pin) and then covered with heatshrink.
B: A larger piece of red heatshrink is ready to be placed over the 2 resistors.
C: Red heatshrink is fitted over the 100R & 10K resistors but not shrunk yet.
The resistors are then soldered to the PS2 socket (data pin) and the red heatshrink is slid over the joint and shrunk.
E: Next the black (GND) and red (+5V) wires are soldered to the PS2 socket.
F: The exposed leads from both the 10K resistors are then bent back ready to be soldered to the red wire/PS2 socket.
G: The 10K resistors are soldered to the red wire at the PS2 socket (+5V).
H: Completed cable.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Links to other interesting threads:
Here is a beta version of the 1-pin Keyboard and 1-pin TV drivers combined in one demo program.
The keyboard requires a the space key (spacebar) to be pressed to synchronise to the program. When this is done, the keyboard sends a <cr> (Enter) to the program to indicate all is well. Characters typed on the keyboard are sent to the TV. Carriage return and scrolling works from the keyboard. Cursor control keys also work. ScrollLock is used for ClearScreen.
Most of the control and cursor movement keys are not being sent (except <cr>) so I will look into this.fixed
The keyboard driver has an internal 16 byte buffer within the cog.
Simply put, the 1-Pin TV driver has the 8x8·font and screen control code·inside the cog. It generates composite video in B&W. The screen buffer is in hub which can be directly accessed by other·programs if required. Basic screen control functions use ASCII commands, not VT100. They are left/right/up/down/backspace/carriage-return/linefeed/home, plus scrolling. Inverse characters are displayed if the bit8=1. A flashing underline cursor is displayed. The format is 40x25 but other combinations are possible by changing the constants inside the source program. A program is included which calculates these constants for you.
Both programs are intended for both the RamBlade and for·SphinxOS, but can just as easily be used to save pins on other prop boards. The demo will run on most standard propboards·using the TV on pins 12-15 and Keyboard on pins 26-27. You do not need to change any of the hardware to test this as the prop will just not output on the unused pins.
An extremely good use for the·TV driver would be for debugging as it only uses 1 pin on the prop and a cog.
I believe all is working as it should be · If you find any bugs please let me know.
There is a translate table in spin in the demo program to translate the keycodes into ascii command codes for the screen control functions. I am not sure where this should go - perhaps in the keyboard driver. There is almost no space in the video, so I don't wnat 2 sets of control characters. Any ideas???
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Links to other interesting threads:
I have just updated the top post with the latest 1pin TV & 1in KBD code. It as been tested up to 6.5MHz overclocking on my RamBlade.
Do not use a twisted pair for the TV & Kbd cable (combined) as it will fail with interference to the keyboard.
This code can be used for a 2pin minimal debug terminal.
Cluso99, just a quick note to let you know that the 1pin driver in obex has an error in the pasm code ... it caused flickering when gotoxy is used. The error looks like a typo to me. fixing it as below removes the flicker. Thank you for the driver - great stuff ...
'do blank lines (top & bottom) doblank MOV VSCL, xsync ' horiz sync (line)
WAITVID xFFOO, #0
MOVI CTRB, #0 ' turn off blank
MOV VSCL, xblank ' line
WAITVID xFFOO, #0
MOVI CTRB, #_iCTRB ' turn on blank
jmpret taskret, taskptr ' to vt100 code
' jmpret taskret, taskptr ' to vt100 code <---- EXTRA LINE TO BE REMOVED
DJNZ rownum, #doblank
doblank_ret RET
I just realised that this extra line was to permit more time for the VT100 style driver. However, my later testing was done with higher clock speeds and overclocking. Just remove this line if you are running at 80MHz.
Sorry to bump an old thread, but I have a question about the 1-pin video driver...
I found the 1-pin video driver was perfect for what I am working on. The inverse video (and gotoxy which wasn't in the original 1-pin video from what I remember) was what finally drew me away from color. For what I was doing, color would have just been for contrast with the background. I am going to overlay the output over a camera image and the basic TV output would have worked fine, but using the extra resources was a problem. 1-pin video was the answer!
But now I am working with a 16x9 format... so 1-pin video at 40x25 has become 1-pin video at 64x28. And at 80Mhz.... hmmm... I lose inverse video. I know I can overclock... but so many other things are already timed to 80 Mhz. Is there any way to get inverse video at 80 Mhz at 64x28? I am willing to give up other features if it is a timing issue. I have already removed the flashing cursor since I don't need it. That gained me approx. 5 assembly instructions! Hee-hee... Yeah, I know... that won't help. But I am open to suggestions.
I even toyed with the idea of just changing the fonts to their inverse which works, but gives up "normal" video out which I might want to use. I would like to keep that option open and sacrifice other options first.
I will change the crystal if I have to but I will be kicking and screaming the whole way! I have 12 sensor inputs and 12 outputs that all are written around 80 Mhz and time dependent.
seeker: The timing is all in a little loop (outputting the actual video section) and from what I recall, I did everything possible to reduce that loop.
However, your comment that everything is timed to the standard clock shouldn't be true. Everything SHOULD be timed to CLKFREQ which is a value loaded into the hub location $0 by the compiler. So, things such as waitcnt (clkfreq/xxx +cnt) will work as stated. The serial objects do the same thing.
BTW I do recall that some of the video code did not comply but that timing could be fixed.
What other objects are you using that you think are not timed correctly?
What resolution are you after? What prop board are you using? Perhaps 96MHz (6MHz) overclocking might work for you - not all boards have been built for overclocking although some could be modified.
I hadn't thought of it that way... I forgot it is all based off of clkfreq, not hard coded time. I am using a 6 channel R/C input, 8 channel PWM servo output, 4 I2C sensors (altimeter, compass, gyro and accelerometer), 2 Pings, TV/audio output, and (as a future option) GPS. Looking at the code closer, you are right. Everything is based off of a divisor of clkfreq. I was over-thinking it and relating to past experience where these things were hard coded timings and even changing one instruction could throw things off.
I want to get 64x28 resolution. It looks great on the 7" TV I use for debugging and the aspect ratio is closer to the 720p video camera signal I want to overlay it on. I am using a Propstick so swapping out the crystal shouldn't be a problem.
Now, where to get a 6 or 6.5 Mhz crystal in Tampa? Hmmmm... I will probably have to order it on line. I was hoping for instant gratification but I guess I will have to wait.
Thanks for the reminder that I am working with a Propeller and not a 6502.
Obviously remove the hubop from the loop (with 80x25 you only have about 44 cycles @80MHz). Then squeeze a bit to make it all fit (don't worry, there is still space left). The scroll code needs more attention, feels like it's too long (picture wobbles even @104MHz, original code).
Attached is a (driver) drop-in replacement for the OBEX package (1.25). This enables all features (up to 80x25 and inverse video) for 80MHz systems. PAL remains untested.
Update:gotoxy now passes the cursor address as part of the command (speedup)
Robiom asked the following by PM...
I could really do with your help. I've just got a new AV monitor which doesn't want to lock on the 1 Pin TV object output. The frame scrolls very slowly down, like the vertical lock is off. Could you point me to the relevant variables so I can "tinker" and hopefully lock the signal.
Many thanks
Rob
Can you answer the following please?
1. What crystal are you using - 5MHz ?
2. What output resistor config are you using ?
3. What screen resolution are you using - 80x24 etc ?
Included in the download should be a spreadsheet that has all the calculations for generating different frequencies.
There is also a writeup at the end of the spin file that talks about the 75ohm termination values that Phil (PhiPi) calculated.
I am wondering if it may be as simple as the signal is not strong enough. You may just need to change the resistor value.
I'm using a 5MHz crystal with system clock of 80MHz. Output is via a 270 ohm resistor in series. The resolution is 60x32 (PAL) but I've dropped it to 40x25 and it does the same. Probably a poor monitor but it does lock on standard video input so slightly confused.
Using the 1.25V release from May of 2010. Is there a newer version? I'll check on obex.
Thanks
Rob
PS I've found a version 1.27 and tried that and exactly the same happens. What I have noticed is, if I change the rows or columns I can make it scroll up or down and at differing speeds......curious.
I've ordered a better monitor as well, just in case
Definitely sounds like the 270 ohm resistor is the problem. The signal level needs to go low enough (close to ground) to trigger a monitor's sync circuitry, and the 270 ohm resistor is probably preventing that. Try shorting it out to see what happens.
This is what Phil recommended (comments at the end of the driver)
The resistor values (124Ω series, 191Ω to ground) have an output impedance of
75 ohms and will drive a 75-ohm load at 1V P-P. The cap is there to filter the
DUTY doody."
Comments
Use a nail gun through the top. Carefully locate it so that you are directly over the third letter of the part number.
As always "X" marks the spot !
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Style and grace : Nil point
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
The code requires a <space> key to be pressed to synchronise to the keyboard speed. Until that happens all keyodes are stripped. Resynchronisation occurs each time a keycode with the LSB (bit 0) = 1 is received.
Currently there is no buffering as I am going to fit the buffers into the cog so that it will work with SphinxOS.
Anyone wishing to test this can do so with no hardware changes to an existing keyboard circuit. This code totally ignores the keyboard clock pin, so only the keyboard data pin is used and utilises the exact same keyboard circuit (10K pullup and 100R series on the keyboard data pin, and a 10K pullup on the keyboard clock pin).
Note: bst is not required for compiling.
Postedit: v116 (code tidyup - no new features)
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
Post Edited (Cluso99) : 1/31/2010 3:17:18 PM GMT
·
You can have one pin for both keyboard and mouse.
·
This 50cents·pdip-8, have 4 inputs/outputs
So 2 pins for keyboard and 2 for mouse.
·
It also have on fixed output, this is the one you use as one wire serial to the prop.
Some custom·Tx UART or·Manchester·will do.
·
http://www.mouser.com/ProductDetail/Freescale-Semiconductor/MC9RS08KA1CPC/?qs=N2XN0KY4UWUndDgeHLAsxA%3d%3d
·
I'm up for the task of programming 25 units when I have the time.
Post Edited (tonyp12) : 1/31/2010 5:27:46 PM GMT
BTW Cog buffer is now working. Next is to add the interface for SphinxOS.
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
It is currently in the form of a standalone test program which requires the serial pc connection to display the keystrokes and a PS2 keyboard connected to P26/P27 although P27 is not used.
The buffer is internal to the cog and it is ready to add into SphinxOS.
Please report any problems. Can be compiled with PropTool.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
For more info, see the RamBlade thread http://forums.parallax.com/showthread.php?p=849265
Keyboard cable (PS2 1-pin version)
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
The keyboard requires a the space key (spacebar) to be pressed to synchronise to the program. When this is done, the keyboard sends a <cr> (Enter) to the program to indicate all is well. Characters typed on the keyboard are sent to the TV. Carriage return and scrolling works from the keyboard. Cursor control keys also work. ScrollLock is used for ClearScreen.
Most of the control and cursor movement keys are not being sent (except <cr>) so I will look into this. fixed
The keyboard driver has an internal 16 byte buffer within the cog.
Information regarding the 1-pin TV Driver is here http://forums.parallax.com/showthread.php?p=822453
Simply put, the 1-Pin TV driver has the 8x8·font and screen control code·inside the cog. It generates composite video in B&W. The screen buffer is in hub which can be directly accessed by other·programs if required. Basic screen control functions use ASCII commands, not VT100. They are left/right/up/down/backspace/carriage-return/linefeed/home, plus scrolling. Inverse characters are displayed if the bit8=1. A flashing underline cursor is displayed. The format is 40x25 but other combinations are possible by changing the constants inside the source program. A program is included which calculates these constants for you.
Both programs are intended for both the RamBlade and for·SphinxOS, but can just as easily be used to save pins on other prop boards. The demo will run on most standard propboards·using the TV on pins 12-15 and Keyboard on pins 26-27. You do not need to change any of the hardware to test this as the prop will just not output on the unused pins.
An extremely good use for the·TV driver would be for debugging as it only uses 1 pin on the prop and a cog.
I believe all is working as it should be
There is a translate table in spin in the demo program to translate the keycodes into ascii command codes for the screen control functions. I am not sure where this should go - perhaps in the keyboard driver. There is almost no space in the video, so I don't wnat 2 sets of control characters. Any ideas???
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
Post Edited (Cluso99) : 2/20/2010 2:06:37 PM GMT
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
Do not use a twisted pair for the TV & Kbd cable (combined) as it will fail with interference to the keyboard.
This code can be used for a 2pin minimal debug terminal.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
Cluso99, just a quick note to let you know that the 1pin driver in obex has an error in the pasm code ... it caused flickering when gotoxy is used. The error looks like a typo to me. fixing it as below removes the flicker. Thank you for the driver - great stuff ...
WAITVID xFFOO, #0
MOVI CTRB, #0 ' turn off blank
MOV VSCL, xblank ' line
WAITVID xFFOO, #0
MOVI CTRB, #_iCTRB ' turn on blank
jmpret taskret, taskptr ' to vt100 code
' jmpret taskret, taskptr ' to vt100 code <---- EXTRA LINE TO BE REMOVED
DJNZ rownum, #doblank
doblank_ret RET
I found the 1-pin video driver was perfect for what I am working on. The inverse video (and gotoxy which wasn't in the original 1-pin video from what I remember) was what finally drew me away from color. For what I was doing, color would have just been for contrast with the background. I am going to overlay the output over a camera image and the basic TV output would have worked fine, but using the extra resources was a problem. 1-pin video was the answer!
But now I am working with a 16x9 format... so 1-pin video at 40x25 has become 1-pin video at 64x28. And at 80Mhz.... hmmm... I lose inverse video. I know I can overclock... but so many other things are already timed to 80 Mhz. Is there any way to get inverse video at 80 Mhz at 64x28? I am willing to give up other features if it is a timing issue. I have already removed the flashing cursor since I don't need it. That gained me approx. 5 assembly instructions! Hee-hee... Yeah, I know... that won't help. But I am open to suggestions.
I even toyed with the idea of just changing the fonts to their inverse which works, but gives up "normal" video out which I might want to use. I would like to keep that option open and sacrifice other options first.
I will change the crystal if I have to but I will be kicking and screaming the whole way!
Any possibility?
Thanks,
-John
However, your comment that everything is timed to the standard clock shouldn't be true. Everything SHOULD be timed to CLKFREQ which is a value loaded into the hub location $0 by the compiler. So, things such as waitcnt (clkfreq/xxx +cnt) will work as stated. The serial objects do the same thing.
BTW I do recall that some of the video code did not comply but that timing could be fixed.
What other objects are you using that you think are not timed correctly?
What resolution are you after? What prop board are you using? Perhaps 96MHz (6MHz) overclocking might work for you - not all boards have been built for overclocking although some could be modified.
I want to get 64x28 resolution. It looks great on the 7" TV I use for debugging and the aspect ratio is closer to the 720p video camera signal I want to overlay it on. I am using a Propstick so swapping out the crystal shouldn't be a problem.
Now, where to get a 6 or 6.5 Mhz crystal in Tampa? Hmmmm... I will probably have to order it on line. I was hoping for instant gratification but I guess I will have to wait.
Thanks for the reminder that I am working with a Propeller and not a 6502.
Thanks for your help... and for a great video driver!
Update: gotoxy now passes the cursor address as part of the command (speedup)
1. What crystal are you using - 5MHz ?
2. What output resistor config are you using ?
3. What screen resolution are you using - 80x24 etc ?
Included in the download should be a spreadsheet that has all the calculations for generating different frequencies.
There is also a writeup at the end of the spin file that talks about the 75ohm termination values that Phil (PhiPi) calculated.
I am wondering if it may be as simple as the signal is not strong enough. You may just need to change the resistor value.
I'm using a 5MHz crystal with system clock of 80MHz. Output is via a 270 ohm resistor in series. The resolution is 60x32 (PAL) but I've dropped it to 40x25 and it does the same. Probably a poor monitor but it does lock on standard video input so slightly confused.
Using the 1.25V release from May of 2010. Is there a newer version? I'll check on obex.
Thanks
Rob
PS I've found a version 1.27 and tried that and exactly the same happens. What I have noticed is, if I change the rows or columns I can make it scroll up or down and at differing speeds......curious.
I've ordered a better monitor as well, just in case
The resistor values (124Ω series, 191Ω to ground) have an output impedance of
75 ohms and will drive a 75-ohm load at 1V P-P. The cap is there to filter the
DUTY doody."
So anything similar to this might help.