Hello FreeCalypso community, This post is a periodic update on what I am doing in the project. Right now I am still working on designing our next development board FC Venus, the one that will serve as a successor to FC Luna for handset fw development purposes. Right now the schematic-level design of this board is tentatively complete:
https://www.freecalypso.org/hg/freecalypso-schem2/ Tentatively complete means that I don't expect to make any further changes to this schematic-level design unless necessitated by part availability difficulties. I have already secured most of the parts needed for this board, and there are currently only a few parts left that are included in the design but which I haven't physically secured yet - if some of these parts turn out to be too difficult to procure, I may need to change the design to use alternative parts that are more readily available, but otherwise it is complete. The current situation with part availability is a nightmare! I am NOT talking about our "special" Calypso parts that have been out of production for almost two decades now and are available only from grey market surplus - those I have secured many years ago in conjunction with FCDEV3B project and earlier, and they are still good for FC Venus. Instead many of our "regular" parts, the ones which anyone could order from Digi-Key at any time in any desired quantity, are now out of stock and available only with insanely long lead times, as in many months to a whole year. In order to secure all of the critical parts that will be needed for the first batch of Venus boards without waiting into the second half of 2022, I had to jump around with alternative sourcing (I strongly prefer Digi-Key, but this time I had to turn to Mouser and Newark for some of the parts), and in some cases switch to different parts which I could grab. FC Venus board can be viewed as consisting of the following major subdivisions: * The Calypso core will be similar to what we built on FCDEV3B, except for a change from triband to quadband, using knowledge gained from reverse eng of iWOW TR-800 modules. * There will be a whole bunch of peripherals: LCD, keypad, magnetic buzzer, 3 different audio channels, battery charging circuit. Some of these peripherals are out of the critical path: if they don't work, or if we have to omit them because parts are missing, the rest of the board will still be useful and valuable to the project. * There will be a built-in FT2232D subsystem for host computer interface to the pair of Calypso UARTs, similar to a built-in DUART28, but slightly simplified given the fixed use case. If this subsystem doesn't work or needs to be omitted because of part shortage, all critical signals are also wired to a 10-pin header to which an external DUART28 adapter can be connected, saving the day. FT2232D chips were particularly hard to get. Right now the official lead time estimate is 2023-01 (yikes), and there are various people on ebay and other marketplaces who sell these chips for as much as $150 each! So how did I get them then? Answer: I called the USA office of FTDI, exchanged emails with their sales team as directed, and they found 100 pcs which they could sell me for a price that was only mildly inflated. (I paid $966.38 after shipping for these 100 pcs of FT2232D, whereas the regular price in a world without shortages is $7.14 apiece for single pieces or $5.32 apiece for qty 100 - so not too terribly inflated, especially compared to what ebay etc sellers are asking.) The complete FT2232D subsystem consists of additional parts beyond the FT2232D chip itself, and right now I have all of those parts secured except the 6.00 MHz crystal. There are plenty of crystals in this frequency in large packages, but my design calls for a low-profile (no more than 1.5 mm height) SMT package, so it can fit inside what I intend to be a shieldcan section. If I am not able to obtain the necessary slim-package crystals in time for the first build of Venus boards, then those boards will have the entire FT2232D subsystem omitted, and I will bring them up using an external DUART28 adapter. Other parts whose in-time availability is currently uncertain reside in the peripheral circuits for the buzzer, the loudspeaker and battery charging. Beyond part sourcing issues, the design of FC Venus is complete at the schematic-equivalent level, but PCB layout hasn't been started yet. I plan to work with the same PCB layout contractor who did our DUART28 and Caramel2 boards last year, but before I can hand the design off to him, I need to create footprints in pcb-rnd format (using new pcb-rnd data model features and conventions) for all components on this board. These pcb-rnd footprints are the next big task I need to work on to bring FC Venus project forward. The LCD module on FC Venus will be Formike KWH020ST23-F01, and the backlight circuit will be MAX1916-based. This LCD module and this backlight circuit have already been proven good on our lunalcd2 board in August of this year. Last month I finally got our custom-made metal bracket parts for securing our LCD module more solidly on "bare" development boards without a phone case, and I got a new lunalcd3 iteration on which this metal bracket will get tested. lunalcd3 PCBs are now on their way to me from China, and I will probably get them assembled shortly after New Year. Finally, there is one critical accessory for FC Venus that is currently being custom-made for us in China: our FC-HDS4 wired headset, discussed here earlier. Earlier this week I sent the payment to the headset manufacturer with the go-ahead to produce 100 pcs of FC-HDS4, and they are now making these headsets. This FC-HDS4 will be a required accessory for FC Venus: the main Iota audio channel (EAR/MIC) will be wired to a 2.5 mm TRRS jack in iWOW's pinout (same as on Caramel2), and the headset will need to be plugged into that jack in order to exercise voice calls and to hear the UI firmware's beeps and whatnot. So that's the current status of FC Venus. Once we get these boards built, assuming that we have good yield and no major design errors, they will be made available to everyone who would be interested in a board for its intended purpose of running FreeCalypso firmware. However, I will NOT support or provide hardware to anyone who would seek to misuse it for the purpose of running OBB crapware. Hasta la Victoria, Siempre, Mychaela aka The Mother _______________________________________________ Community mailing list Community@freecalypso.org https://www.freecalypso.org/mailman/listinfo/community