25.7.: Currently I am hacking with V0.7.10 and V0.7.11of the firmware - things will
28.7.: V0.7.13 ;)
There are two long-button-press key that might be of interest. Buttons are arranged looking at the display face, left three buttons flat, right three button standing out. From upper to lower let's call the left three A, B, C and the right three D, E, F, then:
The hardware consists of two major parts, the watch itself and a charger clip.
The watch is probably based on a TI reference design for the MSP430 and CC2560 low power Bluetooth module. The MSP430 version used in the MetaWacth is a MSP430F5438AIZQWR. More information about the TI-MSP Bluetooth platform can be found here.
It is very annoying that TI itself does not provide any meaningful information about the CC2560 module itself - no datasheet, no extended HCI description, nothing. Judging from the description of the proprietary stack API there must be HCIll commands e.g. to configure / set certain low power states in the module.
A quite remarkable part of the watch is the display, a bi-stable monochrome graphics display with 96x96 pixels. The quite unique part about the display is that it does not display black and not-black, as most monochrome LCD do! Instead it has a mirror on its back so that active pixels which would be black become transparent and by the mirror they become fully reflective. The non active pixels remain dull and do not fully reflect. The effect is that the display looks very unintrusive, stylish and cool! But it has the drawback that it is sometimes a little hard to read, e.g. when something white is reflected.
I am not sure but the display could be a Sharp LS014B4DN02, a datasheet can be downloaded from Mouser Electronics: LS013B4DN02.pdf
And here is the original information on Sharp's web-page.
The power supply is done through a CR2040(?) Lithium-Polymer (LiPoly) coin cell - it is new to me that those exist but very handy!
The watch can be charged and programmed with a four-position connector on the back-side. From top to buttom the pins are
Here are some pics of the hardware.
The charger clip is more than just a simple charger. It contains another TI-MSP430 controller which emulates the TI-MSP430FET debugging and development interface. Using the clip the MSP430 inside the watch can be updated and reprogrammed! And besides of course it will charge the watch's internal battery.
I am hacking on some Linux host side Bluetooth software so that one can control the watch from Linux. The code is still very much in flux so be warned! You can look at it in our labs GIT repo: http://git.kernelconcepts.de/?p=metawatch.git;a=summary
I intend to make that code into a library so that Linux applications can be built upon it and use sort of a simple API to talk to the watch.
Once the firmware for the watch is release we can also start firmware hacking - yeha! For the time being you can already play with the clip's FET and the watch using the latest mspdebug tool. You can connect mspdebug to the watch using the rf2500 driver as described here for the Launchpad - for the MetaWatch this is almost the same. If you really want to be as perfect as possible use the "-v 2500" option to specify 2.5V voltage - but this is rather irrelevant since the clip does not contain any reprogrammable level shifters, it is fixed to 2.5V.
$ mspdebug -v 2500 rf2500 MSPDebug version 0.13 - debugging tool for MSP430 MCUs Copyright (C) 2009, 2010 Daniel Beer
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Trying to open interface 1 on 066 rf2500: warning: can't detach kernel driver: No data available Initializing FET... FET protocol version is 30132072 Configured for Spy-Bi-Wire Set Vcc: 2500 mV Device ID: 0x0580 Device: MSP430F5438A Code memory starts at 0x5c00 Number of breakpoints: 8 Available commands: = dis help locka prog run sym break erase hexout md read set cgraph exit isearch mw regs setbreak delbreak gdb load opt reset step Available options: color gdb_loop iradix quiet Type "help " for more information. Press Ctrl+D to quit. (mspdebug) reset (mspdebug) run Running. Press Ctrl+C to interrupt... ^C ( PC: 061aa) ( R4: 44444) ( R8: 88888) (R12: 03eb6) ( SP: 03fb6) ( R5: 55555) ( R9: 99999) (R13: 0983f) ( SR: 000da) ( R6: 66666) (R10: 00000) (R14: 00014) ( R3: 00000) ( R7: 77777) (R11: bbbbb) (R15: 00001) 061aa: 18 00 MOVA @PC+, R8 061ac: 5a 16 POPM.A #0x5, R10 061ae: 00 13 RETI 061b0: b1 c0 d0 00 00 00 BIC #0xd0, 0x0(SP) 061b6: bf 14 PUSHM.A #0xb, R15 061b8: 40 18 (mspdebug)
The current version of the firmware is based on FreeRTOS with a proprietary Bluetoothstack under IAR. This has some severe disadvantages:
There are thoughts currently being discussed if other open source and low profile Bluetooth stack should be ported / used instead, like
The RAM constraints of the MSP430 are the biggest concerns here. Since the watch also has to keep track of some bitmap buffer for the 96x96 LCD (1152 bytes) and only 16kB being available, this can get pretty tight very fast.
For the time being there are two major obstacles in getting a really free firmware:
Here is a nice tutorial on how to set-up the latest mspgcc with multi-arch support: https://github.com/sergiocampama/Launchpad/blob/master/README.md
It seems that the firmware can get into a pretty hosed state where even a reset, be it hardware or software, does not recover anymore. But rest assured, your watch is not broken!
The MSP430 can be pretty low power, very low power. And some parts of it are static as long as power is supplied. It seems that this error toggles something in a static area that is even kept over reset. But it can be cleared by cutting power - for a long time!
To cut power you have to open the watch - unfortunaletly. But it is not that nasty as it may seem. Removing the battery is not that easy. Best way is to carefully remove the display frame and display. Then you can access the lower battery contacts which you can then isolate using e.g. think plastic straps. After that wait for at least three hours or more - best let it sit over night.
Some clips seem to have issues with the USB interface - ranging from not being detected at all to being detected sometimes. According to my info you can not change that, except by exchanging the clip. On Linux after plugging in the clip you should see something like this in your dmesg:
[218084.712080] usb 3-2: new full speed USB device using uhci_hcd and address 62 [218084.925437] cdc_acm 3-2:1.0: This device cannot do calls on its own. It is not a modem. [218084.925451] cdc_acm 3-2:1.0: No union descriptor, testing for castrated device [218084.925505] cdc_acm 3-2:1.0: ttyACM0: USB ACM device [218091.414002] generic-usb 0003:0451:F432.0017: hiddev0,hidraw1: USB HID v1.01 Device [Texas Instruments Texas Instruments MSP-FET430UIF] on usb-0000:00:1d.1-2/input1
Fossil and TI have analysed that issue and it seems that a software update on the clip can cure that issue. The update though has to be done directly on the hardware and can not be done over USB. So most likely the clip needs to be returned.
Up to watch firmware V0.7.15 there is an issue at least with connecting to Linux BlueZ with enabled SNIFF mode. Once the watch has entered sniff mode the first time it will not exit sniff again causing high latency on any transfer. This can be avoided by disabling sniff mode in the link policy settings on the Linux host, as root-user:
# hciconfig -a hci0 hci0: Type: USB BD Address: 00:19:7E:F7:CD:98 ACL MTU: 1017:8 SCO MTU: 64:8 UP RUNNING PSCAN RX bytes:953 acl:0 sco:0 events:26 errors:0 TX bytes:358 acl:0 sco:0 commands:26 errors:0 Features: 0xff 0xff 0x8f 0xfe 0x9b 0xf9 0x00 0x80 Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3 Link policy: RSWITCH HOLD SNIFF PARK Link mode: SLAVE ACCEPT ---snip---
You can see the "Link policy" as "RSWITCH HOLD SNIFF PARK". You can disable sniff by setting new link policies like this:
# hciconfig hci0 lp RSWITCH,HOLD,PARK
Disabling sniff mode has the disadvantage of higher power consumption on both ends, the watch and the Linux host, with the watch being the more critical party.