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author | Andreas Baumann <mail@andreasbaumann.cc> | 2024-01-27 09:39:02 +0100 |
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committer | Andreas Baumann <mail@andreasbaumann.cc> | 2024-01-27 09:39:02 +0100 |
commit | eb1a6d6c119604853f3af885583fb484812e4d87 (patch) | |
tree | 9c4c7bfb22f11246674e0440fcbe9a3f060f1f27 /content/hardware/imc-2001-keyboard.md | |
parent | da6841100c900f3a1ae47fa1dfaab0618bc33ca3 (diff) | |
download | www-andreasbaumann-cc-eb1a6d6c119604853f3af885583fb484812e4d87.tar.gz www-andreasbaumann-cc-eb1a6d6c119604853f3af885583fb484812e4d87.tar.bz2 |
started to further break down the huge IMC-2001 main article
Diffstat (limited to 'content/hardware/imc-2001-keyboard.md')
-rw-r--r-- | content/hardware/imc-2001-keyboard.md | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/content/hardware/imc-2001-keyboard.md b/content/hardware/imc-2001-keyboard.md new file mode 100644 index 0000000..aaeea43 --- /dev/null +++ b/content/hardware/imc-2001-keyboard.md @@ -0,0 +1,58 @@ ++++ +title = "IMC-2001 keyboard" ++++ + +connector to machine (sort of a rubber version of a DB-9): + +The connector on the computer side has a 9-pin DSUB connector male: + +``` + +----------- white INTR + | +--------- black GND + | | +------- green DATA + | | | +----- blue RESET + | | | | +--- Yellow CLOCK +------------- +\ O O O O O / + \ O O O O / + --------- + | | | +---- red 5V + | | +------ n.c. + | +-------- n.c. + +---------- n.c. +``` + +On the keyboard PCB there is a strange white connector with the following layout: + +``` + +------------- white INTR (active low, after last clock tick) + | +----------- black GND + | | +--------- blue RESET (active low) + | | | +------- green DATA + | | | | +----- yellow CLOCK + | | | | | +--- red +5V + +-----------+ + |o o o o o o| + +-----------+ + | | +``` + +Keyboard layout: + +{{< figure src="/images/hardware/imc-2001/keyboard_front.jpg" alt="keyboard layout" >}} + +Keyboard has a 8039 CPU inside and a 2K EPROM: + +{{< figure src="/images/hardware/imc-2001/keyboard_pcb_controller_prom.jpg" alt="PCB and controller" >}} + +On the oscilloscope: + +{{< figure src="/images/hardware/imc-2001/oscilloscope_serial_keyboard.jpg" alt="serial keyboard signal" >}} + +The protocol is basically ASCII over 19200 baud serial, with an interesting end signal which +IMHO triggers a latch on the motherboard or so (INTR white above). + +Broken keyboard cable (the black pins are just connectors added by me to test connectivity, +both connector are female per default): + +{{< figure src="/images/hardware/imc-2001/keyboard_cable.jpg" alt="PCB and controller" >}} |