Hello FreeCalypso community, Right now there is a possibility that I may be reopening the idea of producing a "FreeCalypso Lite" phone by way of aftermarket firmware running on historical Motorola C139/140 hardware; the purpose of this announcement is to gauge whether or not there is still any community interest in this idea.
We have had non-practically-usable proof-of-concept FC firmware that runs untethered with a primitive PoC UI on C139 hw since 2015, and since 2018 we have had rock-solid lower layers for this target, namely fully compliant GSM radio operation using original factory calibration data and battery charging using our own FreeCalypso original driver. For the past two years, the *only* missing piece has been high-level UI firmware work, i.e., the work to fix various bugs in TI's demo/ prototype UI code and bring it up to par. During all of the time up to now, I have been very reluctant to make heavy-duty changes to TI's demo/prototype UI code (the kind of heavy- duty changes that would be needed in order to bring it up to par and make it practically usable as a phone) because I was not and still am not willing to give up the other "big color" configuration. TI's PoC UI code can be built in two configurations, targeting either the large color 176x220 pixel display on TI's D-Sample platform, or the small black&white 84x48 pixel display from TI's earlier platforms, meaning C-Sample and earlier. The PoC UI which we got running on Mot C139 hw is the C-Sample version; further work can be done on this "small B&W" UI version to extend it from 84x48 to 96x64 pixels (C1xx display size), but the part which I was absolutely not willing to do (and still am not) is to work *solely* on the small screen version of the UI, permanently giving up on "big color" version and thus permanently giving up my dream of some day building a true FreeCalypso phone - no way will I ever give that dream up! And because up until now we did not have any workable development platform with a 176x220 pixel color LCD connected to a Calypso core, all UI work ideas stood at a halt, making no progress in any direction, C139 or otherwise. But during the past few months there has been a breakthrough, and there now exists a new in-house development platform here at FreeCalypso HQ, a platform which I have named FC Luna. Back in December our dear Das Signal obtained two pieces of a very rare Calypso development board (made by a non-TI third party) which we have codenamed Caramel; this Caramel board has a Leonardo clone as its core (thus trivially supported by FreeCalypso with fully working GSM radio), plus one more very special feature: it has an expansion interface on which many Calypso signals are brought out, including the 16-bit memory bus (MEMIF) to which one can connect an LCD module with a memory-mapped microprocessor bus interface, i.e., an LCD of the same class as on TI's D-Sample and on the Pirelli DP-L10. The new Luna UI development platform that has been put together at FreeCalypso HQ consists of a Caramel board that has been reworked by my friends at Technotronix to change the expansion interface to an easier-to-work-with connector type, plus the Luna LCD carrier board (add-on piece) that was designed and built by me, connected to the expansion interface on the modified Caramel board with a hand-made (custom pinout) ribbon cable. The actual LCD module is a HaoRan HT020K1QC36S, one of the several LCD modules which I had evaluated back in 2018 and one of the two which I found to be good; it is a 176x220 pixel 16-bit color LCD with a 16-bit microprocessor bus interface. My custom hardware hacking ministrations result in this nice LCD being connected to Calypso MEMIF on the modified Caramel board and mapped into Calypso address space; FC Magnetite firmware built for target luna runs on this platform and successfully displays TI's original 176x220 pixel color UI on my Luna LCD, all while having a fully working GSM radio at the same time! Unfortunately I won't be able to share this Luna hw platform with the community: while the Luna add-on piece designed by me can be produced very cheaply and easily (the design files live in the fc-small-hw Hg repository), it is rather useless without the Caramel motherboard, and of the latter there are only two in the world - I have one and DS has the other. But while I am not able to share the development platform itself, I am hoping to be able to use this dev platform to produce some fruits which *can* be shared - and one possible fruit which I might be able to produce would be FreeCalypso on C139 brought to a practically usable state. This new Luna platform has been put together into its working state just earlier this week, and now is the first time in all of the years of FreeCalypso that I've been able to run the "big color" version of TI's PoC UI on a platform with working GSM radio (unlike the original D-Sample board) and with instantaneous updates on the directly connected LCD - as opposed to many seconds of lag when I tried reading out the firmware's framebuffer over serial in the absence of a physical display. This is the first time in years that we are able to run TI's original UI code in all of its glory, in all available configurations: the "big color" config on the Luna platform, and the "small B&W" config on both Luna and C139. How will Luna help FC-on-C139 development? My idea is as follows: now that I can run the UI code in both "big color" and "small B&W" configs, I can make bugfixes and other changes, and test both configs at each step. I reason that I should be able to work on the "small B&W" config that runs on the C139, but thanks to Luna platform, do it in such a way that does not break the "big color" UI config, leaving the possibility open for my desired FreeCalypso dream phone. I do need to set the expectations clear, though: for me personally, Mot C139 running FreeCalypso fw can *never* replace my dream of a true FreeCalypso phone (meaning phone handset hw designed by me, with me rather than Motorola or some other historical manuf making every key design decision), thus the scope of the work which I would be willing to do for C139 on a volunteer basis (outside of paid contract terms) will always be limited. In particular, I am currently thinking of keeping the small 96x64 pixel UI black & white - the physical LCD on the C139 is 16-bit color (not sure if it is CSTN or TFT), but the only "small" (smaller than 176x220 pixels) UI we got from TI is B&W. I currently feel that extending TI's "small B&W" UI from 84x48 to 96x64 pixels would be a significantly smaller job than designing a new 96x64 pixel color UI - the latter would involve significantly more creative work, it seems to me based on my current understanding. I can certainly do it, but because Motorola hw is very uninspiring to me personally, I currently feel that designing a 96x64 pixel color UI would be something I would do only under a contract gig - whereas the "all volunteer" version I am currently contemplating would be B&W only. So what I am currently considering is developing a rather basic and limited "FreeCalypso Lite" firmware for C139: it would be limited in the sense of having no UI colors, no fancy ringtones beyond the most basic, no other frills - but I would fix the critical bugs (crashing etc) and add the parts of essential functionality which are currently missing. Anything else can be added later: the most basic minimal functionality will need to be developed first, and right now we don't have even that. But here is the critical question: would anyone in our community be interested in a working and practically usable (albeit very minimal) FreeCalypso firmware version running on C139 hardware in 2020? There will be a much higher likelihood of me actually carrying through this time - as opposed to dropping it again - if there is at least one person seriously interested. Thus if there is anyone still interested in FC firmware for Mot C139 and who would be willing to use it as his or her personal phone if I get it into a practically usable state, please speak up! Hasta la Victoria, Siempre, Mychaela aka The Mother _______________________________________________ Community mailing list [email protected] https://www.freecalypso.org/mailman/listinfo/community
