Search found 325 matches

by MMcM
21 Nov 2022, 01:37
Forum: Workshop
Topic: IO expanders with RP2040
Replies: 15
Views: 4930

Re: IO expanders with RP2040

The data sheet seems to say that max output low (D080) is 0.6V, max input low (D031) is 0.2 Vdd = 0.6V @ 3V, min input high (D041) is 0.8 Vdd = 2.4V @3V. So it doesn't seem that 0.07V should be confusing anything. Maybe just go ahead and code up the matrix to set input pullups and one output low and...
by MMcM
13 Nov 2022, 23:54
Forum: Workshop
Topic: IO expanders with RP2040
Replies: 15
Views: 4930

Re: IO expanders with RP2040

spi_start doesn't actually communicate with the external device; it just configures the internal SPI to talk to it. So success just means no internal pin conflicts. You should look at the return value from spi_receive. If I am not mistaken, the only time this device will send you anything is when yo...
by MMcM
13 Nov 2022, 17:24
Forum: Workshop
Topic: IO expanders with RP2040
Replies: 15
Views: 4930

Re: IO expanders with RP2040

Oh, yes, you are absolutely right. I apologize for giving unsafe advice.

Just change the direction when scanning to set one low.
by MMcM
13 Nov 2022, 04:45
Forum: Workshop
Topic: IO expanders with RP2040
Replies: 15
Views: 4930

Re: IO expanders with RP2040

I assume you are following https://github.com/qmk/qmk_firmware/blob/master/docs/spi_driver.md and https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MCP23008-MCP23S08-Data-Sheet-DS20001919.pdf. Overall, I would expect: Two address pins are hardwired to fix SP...
by MMcM
18 Jun 2022, 16:45
Forum: Workshop
Topic: Wey MK06 without Connector Box
Replies: 7
Views: 2453

Re: Wey MK06 without Connector Box

In order to get all this working properly, the MK06 workstation needs to be configured to use the proper keycode table (KCT file). PCSIN001 is a good choice to start with: it has all the "standard" codes for the PC layout, which means that the translation to PS2 scan set 2 that happens on the TTL C/...
by MMcM
18 Jun 2022, 16:44
Forum: Workshop
Topic: Wey MK06 without Connector Box
Replies: 7
Views: 2453

Re: Wey MK06 without Connector Box

The global chip shortage got me thinking, though, about going outside the QMK ecosystem to CircuitPython. So, here is one with an Itsy-Bitsy M4 Express using the Atmel SAMD51. Wey-M4-converter.jpg Wey-M4-cable.jpg Wey-M4-converter-operating.jpg Now suppose one actually wanted a KVM (well K+M) keyboa...
by MMcM
18 Jun 2022, 16:39
Forum: Workshop
Topic: Wey MK06 without Connector Box
Replies: 7
Views: 2453

Re: Wey MK06 without Connector Box

A converter specifically for the MK06 interfaces to one of the serial ports. This could be directly to Port 4 or Port 5 and so implementing a single workstation. More interesting is to implement the DLINK protocol and so work for multiple workstations, possibly with different layouts or function key...
by MMcM
18 Jun 2022, 16:36
Forum: Workshop
Topic: Wey MK06 without Connector Box
Replies: 7
Views: 2453

Re: Wey MK06 without Connector Box

The easiest way to interface without a Connector Box is using PS2. Get an MDR 36 male connector from AliExpress or eBay. Build a cable that gives 12VDC from a wall wart to the two ends of the connector (- 1,19, + 18,36) and wires a 6-pin mini-DIN male (cut up an old cable) to Port 1 Clock, Data, and...
by MMcM
18 Jun 2022, 16:34
Forum: Workshop
Topic: Wey MK06 without Connector Box
Replies: 7
Views: 2453

Wey MK06 without Connector Box

The MK06 is a now obsolete KVM switching keyboard that can emulate a variety of trading keyboards. It is full-size, with three small LCD screens and two add-on keypads. The trading function keys tend to be garishly colored. The actual host connections, such as USB or PS2, as well as power for the ke...
by MMcM
29 Apr 2022, 17:48
Forum: Workshop
Topic: Cortron (ITW) 55-500216
Replies: 10
Views: 4266

Re: Cortron (ITW) 55-500216

I admit I have never seen the typewriter style, but I believe yours is another variant of keypunch, adding | and losing { and }. Compare with this , for instance, particularly keys 20-29. More details on the converter here . Do take note of the limitations of such a non-destructive conversion, though.
by MMcM
28 Apr 2022, 04:21
Forum: Workshop
Topic: My Deko Fast Action Keyboard project
Replies: 17
Views: 8027

Re: My Deko Fast Action Keyboard project

In case you're wondering, it's all PS2: Extra keys: .---.---. .---. .---.---.---.---. .---.---.---.---. .---.---. .---.---. .---.---. | 60| 17| | 1F| | 27| 2F| 37| 3F| | 56| 5E| 6F| 13| | 19| 39| | 51| 53| | 5C| 62| +---+---+ +---+ +-----+ .-------. .---. .---------------. .---------------. .-------...
by MMcM
25 Apr 2022, 04:06
Forum: Workshop
Topic: Cortron (ITW) 55-500216
Replies: 10
Views: 4266

Re: Cortron (ITW) 55-500216

The keyboard for the Sperry-Univac UDS-2000, pictured in the Wiki , uses a similar PCB, Cortron 55-500252. It comes in three styles , typewriter, adding machine, and keypunch. The photos in the Wiki are of the adding machine style, with 0 at the bottom (replacing part of the space bar). Here is the ...
by MMcM
18 Apr 2022, 05:32
Forum: Workshop
Topic: IR PC keyboards: IBM and Quadram
Replies: 6
Views: 3100

Re: IR PC keyboards: IBM and Quadram

An NEC product in this space is the PC-6601SR, aka Mr. PC. The keyboard can use infrared or a coiled cable, switching modes depending on whether it is plugged in. NEC-6601SR-case.jpg Someone has completely documented how this PC works, including schematics , keyboard scan codes , and keyboard protoc...
by MMcM
18 Mar 2022, 01:17
Forum: Workshop
Topic: Hi-Tek 725 terminal keyboard
Replies: 13
Views: 4882

Re: Hi-Tek 725 terminal keyboard

I've been working on decoding the ADDS protocol recently Maybe not the same protocol, but did you see this ? Code for that is here . I see that you have uploaded the ADDS ASCII firmware to Bitsavers (thanks), so reading that (or looking at traces where a real terminal is connected) should be enough...
by MMcM
13 Mar 2022, 22:24
Forum: Keyboards
Topic: Nixdorf Keyboard
Replies: 12
Views: 4153

Re: Nixdorf Keyboard

Okay, I had a chance to look at a G80-0801. First, to make sure that the numbering is consistent. I believe that in the close-up photo on Google Drive linked to above, it shows how S1 is numbered, with 1 at the top-left then 2 beside it. I therefore read the pinout as follows. S1:2 - DE-9:1 - green ...
by MMcM
09 Feb 2022, 18:44
Forum: Workshop
Topic: Consul 262.4
Replies: 0
Views: 1055

Consul 262.4

I do not have one of these keyboards, but I do have a Consul 262.3 and was asked about the difference and the possibility of converting the 262.4. Here are some notes on that. The short version, as noted in passing here is that the 262.3 is a parallel ASCII keyboard and the 262.4 is the serial versi...
by MMcM
23 Jan 2022, 19:30
Forum: Keyboards
Topic: Look at this Cool Find (Memorex 2051 Terminal Keyboard)
Replies: 6
Views: 6322

Re: Look at this Cool Find (Memorex 2051 Terminal Keyboard)

From the photos (and a few more clearer ones), it is possible to mostly work out how this operates. It also helps to understand how the 5251 keyboard communicates, because some of those ideas were borrowed, too. Program 8048 microcontroller (4) 74373 latch (2) and PROM (3) implement extended program...
by MMcM
17 Jan 2022, 06:27
Forum: Workshop
Topic: Sharp X1 Turbo
Replies: 0
Views: 7905

Sharp X1 Turbo

This keyboard is for a Sharp X1 Turbo. Sharp-X1-case.jpg This particular model, DSETK0011CE00, has green Alps, so it is nice enough to type on, but thankfully not yet a target for those harvesting switches. The lock keys are physically locking; there are no indicators. Sharp-X1-back.jpg The cable te...
by MMcM
08 Jan 2022, 06:55
Forum: Want to buy
Topic: [WTB][EU-HU] Deko Fast Action
Replies: 1
Views: 2173

Re: [WTB][EU-HU] Deko Fast Action

When you get one, I can pass along the extra PS/2 codes that control the small-button LEDs and the VFD.
by MMcM
08 Jan 2022, 06:48
Forum: Want to buy
Topic: [WTB] Keyboard and mouse for an Apollo Domain Series 3000
Replies: 8
Views: 5872

Re: [WTB] Keyboard and mouse for an Apollo Domain Series 3000

Well, I can confirm (and the Technical Reference does, too) that the mouse connector on the back of the keyboard is DE-9 F, so it will at least fit. The keyboard firmware reads that raw mouse and in turn encodes it within a 1200 baud TTL-level serial keyboard+mouse protocol that talks to the system.
by MMcM
08 Jan 2022, 06:15
Forum: Want to buy
Topic: [WTB] Keyboard and mouse for an Apollo Domain Series 3000
Replies: 8
Views: 5872

Re: [WTB] Keyboard and mouse for an Apollo Domain Series 3000

The Apollo mouse is not like serial PC mice: even though it uses a DE-9, it isn't RS-232.

It's like the original Macintosh mouse, exposing X- and Y-quadrature lines directly, along with the buttons. Although the pinout isn't the same.

See here.
by MMcM
01 Jan 2022, 02:19
Forum: Workshop
Topic: Xerox 820-II Keyboards
Replies: 0
Views: 10473

Xerox 820-II Keyboards

When a keyboard has a 25-pin D-sub connector, it generally has some kind of parallel output. Occasionally, this is the raw switch matrix connections. Or it can have four inputs to a row selector and outputs for the column states in the row so selected. These cases are easy to recognize by what activ...
by MMcM
26 Dec 2021, 22:49
Forum: Workshop
Topic: ADDS ASCII in ADDS Mode
Replies: 1
Views: 8428

ADDS ASCII in ADDS Mode

ADDS ASCII keyboards have four sets of jumpers that switch between PC/AT and ADDS mode. I believe most people just check these, replace with PC mode when necessary, and use the board with Soarer's converter, end of story. But what if one doesn't replace them or does so in the opposite direction? I i...
by MMcM
20 Dec 2021, 06:09
Forum: Keyboards
Topic: Sanyo MBC 550 conversion
Replies: 1
Views: 4152

Re: Sanyo MBC 550 conversion

It's 1200 baud serial ASCII. See https://geekhack.org/index.php?topic=86197.0.
by MMcM
24 Nov 2021, 05:38
Forum: Workshop
Topic: Convergent Technologies and Negative Serial
Replies: 14
Views: 16808

Re: Convergent Technologies and Negative Serial

This is a keyboard for a Sperry-Univac UTS terminal. UTS-case.jpg I believe that this is the so-called Low Profile Expanded Typewriter keyboard. UTS-back.jpg It is Key Tronic foam and foil. The foam on this particular one (from around 1988) is substantially intact, so I have not yet undertaken repla...
by MMcM
22 Nov 2021, 21:18
Forum: Workshop
Topic: Some parallel ASCII keyboards
Replies: 7
Views: 12838

Re: Some parallel ASCII keyboards

Another 55SW board with the same thick doubleshot keycaps with ASCII control legends. 55SW1-10-top.jpg This is SW-11769 / 55SW1-10. 55SW1-10-side.jpg The parallel output on the edge connector is substantially the same as SW-11234 / 55SW5-2 above, though the STROBE signal is not inverted (so rising t...
by MMcM
21 Nov 2021, 22:02
Forum: Keyboards
Topic: Which generation of Fujitsu Leaf Spring is this?
Replies: 12
Views: 4804

Re: Which generation of Fujitsu Leaf Spring is this?

Reimu64 wrote:
21 Nov 2021, 21:45
I have no idea what 61, 62 or 63 stands for.
Showa 62 is 1987.
by MMcM
17 Nov 2021, 04:43
Forum: Keyboards
Topic: Need help! Which switches is it??
Replies: 2
Views: 1086

Re: Need help! Which switches is it??

Check the wiki.
by MMcM
15 Nov 2021, 07:05
Forum: Workshop
Topic: Convergent Technologies and Negative Serial
Replies: 14
Views: 16808

Re: Convergent Technologies and Negative Serial

Converting a Sun Type 3 keyboard got me revisiting how that converter works again. The existing one, as described above, which originally ran its own firmware project, but now has QMK configured for hardware serial -- there is an inverter -- isn't really suitable for a DA-15. Sun-45-converter.jpg So...
by MMcM
25 Oct 2021, 08:09
Forum: Workshop
Topic: Some parallel ASCII keyboards
Replies: 7
Views: 12838

Re: Some parallel ASCII keyboards

Another Maxi-Switch linear. This one is 2160094, with PCB 630010-10. Maxi-Switch-2160094-top.jpg Maxi-Switch-2160094-bottom.jpg A general purpose microcontroller is used in place of just a converter, but there isn't anything interesting going on with the output encoding. It has both an edge connecto...

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