mirror of
https://github.com/qmk/qmk_firmware.git
synced 2024-11-27 21:50:12 +00:00
3f96ba0113
* Initial palm_usb support * removing left over sun .c file * fixing licenses * actually adding updated files * fixing build error * more include cleanup
97 lines
3.4 KiB
Markdown
97 lines
3.4 KiB
Markdown
# Stowaway Serial keyboard to USB protocol converter
|
|
|
|
A converter for Palm Pilot era Stowaway serial keyboards.
|
|
|
|
Makes extensive use of the code from [cy384](https://github.com/cy384/ppk_usb). Ported to QMK by [milestogo](https://github.com/milestogo).
|
|
|
|
Hardware Supported: See hardware section below
|
|
Hardware Availability: self-built
|
|
|
|
Make example for this keyboard (after setting up your build environment):
|
|
|
|
make converter/palm_usb/stowaway:default
|
|
|
|
See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
|
|
|
|
|
|
## Hardware
|
|
|
|
Target MCU is ATMega32u4 but other USB capable AVRs should also work.
|
|
|
|
cy843 has a very specific way of wiring in order to fit all pins in sequence. It breaks
|
|
qmk because the Arduino softserial library uses different pins from QMK.
|
|
|
|
I've wired the pro micro hardware as follows.
|
|
|
|
Label| TX0,RX1,GND,GND,2 ,3 ,4 ,5 ,6 ,7
|
|
Palm | , , * ,GND,VCC,RX ,NC ,RTS,nc ,DCD
|
|
MCU | ,D1 ,D0 , ,C6 , ,E6
|
|
|
|
\* The RX line from the keyboard should be conected to a ~10K ohm pull down resistor to ground.
|
|
RX --|--3
|
|
10K
|
|
|
|
|
GND
|
|
|
|
|
|
Power management is not implemented yet, this just reboots the keyboard frequently.
|
|
|
|
### Keyboards:
|
|
|
|
Think Outside Stowaway Keyboards
|
|
There are at least 5 different versions of these keyboards out there.
|
|
|
|
Group 1: Palm 3, Palm 5 & HP Journada 540, and Compaq iPaq keyboards. These share
|
|
the same RTS protocol, but with different pinouts for each device.
|
|
|
|
Group 2: Handspring keyboards. These don't do handshaking protocol, and use TTL signal.
|
|
Set HANDSPRING to 1 in config.h
|
|
|
|
Group 3: IRDA models. Untested but theoretically serial.
|
|
|
|
### Connectors
|
|
|
|
See https://github.com/cy384/ppk_usb for wiring & sample 3d printable sockets.
|
|
|
|
Only Palm3 wiring has been tested.
|
|
RXD pin is output from keyboard to MCU's RX.
|
|
|
|
Viewed from left to right with the keyboard in typing position.
|
|
|
|
Palm3: [NC, VCC, RXD, RTS, NC, NC, DCD, NC, NC, GND]
|
|
Palm5: [NC, VCC, RXD, RTS, NC, NC, DCD, NC, NC, GND] (same order, different connector)
|
|
Handspring: [VCC/TXD, NC, NC, NC, GND, NC, NC, RXD]
|
|
Journada: [NC, NC, NC, GND, NC, RTS, NC, DTR/VCC, RXD, DCD, NC] [GND-IN, VCC-IN]
|
|
Ipaq: [NC, NC, DTR/VCC, NC, NC, RTS, NC, RXD, DCD, GND, NC, NC]
|
|
|
|
### Protocol
|
|
|
|
Signal: Asynchronous, Negative logic, 9600baud, No Flow control
|
|
Frame format: 1-Start bit, 8-Data bits, No-Parity, 1-Stop bit
|
|
|
|
AVR USART engine expects positive logic while stowaway keyboard signal is negative.
|
|
To use AVR UART engine you need external inverter in front of RX and TX pin.
|
|
Otherwise you can software serial routine to communicate the keyboard.
|
|
|
|
This converter uses software method, you doesn't need any inverter part.
|
|
|
|
|
|
Commands From System To Keyboard
|
|
none
|
|
|
|
Commands From Keyboard To System
|
|
|
|
0xFA Reset/Ready Response(followed by 0xFD)
|
|
|
|
References
|
|
|
|
* http://www.splorp.com/pdf/stowawayhwref.pdf
|
|
|
|
### Todo
|
|
- Test on anything but a palm 3 model keyboard.
|
|
- Change all of the soft serial to match the new Helix based code so that it is easier
|
|
to switch pins.
|
|
- The driver should check for a keyboard that pressed the delete key then disconnected.
|
|
Check every MAXDROP scans that the keyboard is there, and if not, clear the matrix.
|
|
Not implemented yet, since matrix scan is so much faster than serial.
|