Re: [vcf-midatlantic] much ado about chording keyboards
Thanks Jeff. To give context to this discussion, I built a chording keyboard for my Replica 1 and Apple 2+ by interfacing an Arduino to the keyboard socket and using 5 arcade momentary switches from Micro Center. I coded it so that my fingers chord a hex nibble and the thumb strobes it into the Arduino, and the LED shows whether you are chording the high nibble or low nibble. It is possible to recode it for other chording mechanisms and add switches to choose a mode. Eric
On 9/29/2019 1:14 PM, Eric Rangell via vcf-midatlantic wrote:
Thanks Jeff. To give context to this discussion, I built a chording keyboard for my Replica 1 and Apple 2+ by interfacing an Arduino to the keyboard socket and using 5 arcade momentary switches from Micro Center. I coded it so that my fingers chord a hex nibble and the thumb strobes it into the Arduino, and the LED shows whether you are chording the high nibble or low nibble. It is possible to recode it for other chording mechanisms and add switches to choose a mode. Eric
Eric, that reminds me: did you ever get a chance to probe out all the outputs of the GI "AY-5-3600-931-B6" (second sourced as SMC "331-0931-B KR3600-070" ) from the early apple2/plus keyboard, for every possible keyboard input, shift+input, ctrl+input and shift+ctrl+input combination? I.e. what data in B1-B10 (pins 14 down to 5) is returned, if any, for every possible unique X-bus output (on pins 40 down to 32) and for each unique X-bus output, every possible Y-bus input (on pins 26 down to 17); this whole process gets repeated 4 times, with neither shift (pin 29) nor control (pin 28) asserted, shift asserted, control asserted, and both shift+control asserted. See http://www.bitsavers.org/components/gi/_dataBooks/1980_GI_Microelectronics_D... page 3-23 (pdf page 134) I'm trying to improve the accuracy of the apple2 keyboard emulation in MAME/MESS. As far as I'm aware, the 331-0931-B uses the very last mask option on the list, where pin 4 is AKO and pin 5 is B10. I'm guessing these tests will require an arduino mega to read the 9 X-bus outputs in a fast loop and sequentially supply a 10-bit y-bus input when the x-bus reaches the correct 'count' being probed, and immediately after that either poll the AKO pin, and if it goes active, immediately read the 10-bit B bus, or just read the 10-bit bus and assume it detected a key-down. -- Jonathan Gevaryahu jgevaryahu@gmail.com jgevaryahu@hotmail.com
On 10/1/2019 10:24 PM, Jonathan Gevaryahu wrote:
On 9/29/2019 1:14 PM, Eric Rangell via vcf-midatlantic wrote:
Thanks Jeff. To give context to this discussion, I built a chording keyboard for my Replica 1 and Apple 2+ by interfacing an Arduino to the keyboard socket and using 5 arcade momentary switches from Micro Center. I coded it so that my fingers chord a hex nibble and the thumb strobes it into the Arduino, and the LED shows whether you are chording the high nibble or low nibble. It is possible to recode it for other chording mechanisms and add switches to choose a mode. Eric
Eric, that reminds me: did you ever get a chance to probe out all the outputs of the GI "AY-5-3600-931-B6" (second sourced as SMC "331-0931-B KR3600-070" ) from the early apple2/plus keyboard, for every possible keyboard input, shift+input, ctrl+input and shift+ctrl+input combination?
I.e. what data in B1-B10 (pins 14 down to 5) is returned, if any, for every possible unique X-bus output (on pins 40 down to 32) and for each unique X-bus output, every possible Y-bus input (on pins 26 down to 17); this whole process gets repeated 4 times, with neither shift (pin 29) nor control (pin 28) asserted, shift asserted, control asserted, and both shift+control asserted.
See http://www.bitsavers.org/components/gi/_dataBooks/1980_GI_Microelectronics_D... page 3-23 (pdf page 134)
I'm trying to improve the accuracy of the apple2 keyboard emulation in MAME/MESS.
As far as I'm aware, the 331-0931-B uses the very last mask option on the list, where pin 4 is AKO and pin 5 is B10.
I'm guessing these tests will require an arduino mega to read the 9 X-bus outputs in a fast loop and sequentially supply a 10-bit y-bus input when the x-bus reaches the correct 'count' being probed, and immediately after that either poll the AKO pin, and if it goes active, immediately read the 10-bit B bus, or just read the 10-bit bus and assume it detected a key-down.
As it turns out, Sean Riddle decapped one of these, so it should be possible to create an exact replica on a microcontroller, or out of an ay-5-3600-pro... and it also turns out, about a week ago, someone dumped the eprom from a clone apple2/2+ keyboard which DOES use an ay-5-3600-pro plus an eprom, see https://www.applefritter.com/content/clone-keyboard-eprom-data-intact So between those two things, it should be very possible to make a replacement part/board for burned out SMC KR3600-070 or AY-5-3600-070 or 331-0931-B parts. -- Jonathan Gevaryahu jgevaryahu@gmail.com jgevaryahu@hotmail.com
On 11/29/2019 4:40 AM, Jonathan Gevaryahu wrote:
On 10/1/2019 10:24 PM, Jonathan Gevaryahu wrote:
On 9/29/2019 1:14 PM, Eric Rangell via vcf-midatlantic wrote:
Thanks Jeff. To give context to this discussion, I built a chording keyboard for my Replica 1 and Apple 2+ by interfacing an Arduino to the keyboard socket and using 5 arcade momentary switches from Micro Center. I coded it so that my fingers chord a hex nibble and the thumb strobes it into the Arduino, and the LED shows whether you are chording the high nibble or low nibble. It is possible to recode it for other chording mechanisms and add switches to choose a mode. Eric
Eric, that reminds me: did you ever get a chance to probe out all the outputs of the GI "AY-5-3600-931-B6" (second sourced as SMC "331-0931-B KR3600-070" ) from the early apple2/plus keyboard, for every possible keyboard input, shift+input, ctrl+input and shift+ctrl+input combination?
I.e. what data in B1-B10 (pins 14 down to 5) is returned, if any, for every possible unique X-bus output (on pins 40 down to 32) and for each unique X-bus output, every possible Y-bus input (on pins 26 down to 17); this whole process gets repeated 4 times, with neither shift (pin 29) nor control (pin 28) asserted, shift asserted, control asserted, and both shift+control asserted.
See http://www.bitsavers.org/components/gi/_dataBooks/1980_GI_Microelectronics_D... page 3-23 (pdf page 134)
I'm trying to improve the accuracy of the apple2 keyboard emulation in MAME/MESS.
As far as I'm aware, the 331-0931-B uses the very last mask option on the list, where pin 4 is AKO and pin 5 is B10.
I'm guessing these tests will require an arduino mega to read the 9 X-bus outputs in a fast loop and sequentially supply a 10-bit y-bus input when the x-bus reaches the correct 'count' being probed, and immediately after that either poll the AKO pin, and if it goes active, immediately read the 10-bit B bus, or just read the 10-bit bus and assume it detected a key-down.
As it turns out, Sean Riddle decapped one of these, so it should be possible to create an exact replica on a microcontroller, or out of an ay-5-3600-pro...
and it also turns out, about a week ago, someone dumped the eprom from a clone apple2/2+ keyboard which DOES use an ay-5-3600-pro plus an eprom, see https://www.applefritter.com/content/clone-keyboard-eprom-data-intact
So between those two things, it should be very possible to make a replacement part/board for burned out SMC KR3600-070 or AY-5-3600-070 or 331-0931-B parts.
Whoops, I forgot the link to Sean Riddle's decap: https://seanriddle.com/kr3600.html -- Jonathan Gevaryahu jgevaryahu@gmail.com jgevaryahu@hotmail.com
participants (2)
-
Eric Rangell -
Jonathan Gevaryahu