FreeCalypso > hg > freecalypso-docs

annotate FCDEV3B-repackaging @ 4:1dbc8c5d9698

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
FCDEV3B-repackaging: triband vs. quadband section added
author Mychaela Falconia <falcon@freecalypso.org>
date Wed, 10 Oct 2018 17:22:57 +0000
parents 4f873ec004f6
children f920c9a68d45
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
2
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 Repackaging FreeCalypso modem into different physical form factors
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 ==================================================================
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 As of this writing, our FreeCalypso Triband Modem Solution has reached the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 status of a finished product: it is no longer experimental or developmental,
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 it is now fully fit for operational use on live public GSM networks in end user
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 applications that need a standards-compliant GSM+GPRS modem. However, at the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 present moment it is only available in the physical form factor of a development
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 board (FCDEV3B) that was originally designed to serve as a software/firmware
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 development platform, and as such it is not ideally suited for use as an end
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 product. For end use applications it would be highly desirable to take our
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 proven FC Triband Modem Solution (FC-TMS) as realized on the FCDEV3B and
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 repackage it into other physical form factors. This repackaging can be done
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 in two ways:
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 Approach 1 (strongly preferred): the party who desires to have our FC-TMS in a
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 particular form factor gets in touch with FreeCalypso Central, engages in a
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 discussion with us to arrive at the new form factor to be implemented (it needs
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 to satisfy your requirements and be feasible for us to implement), then funds
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 the cost of PCB layout labor to turn the new form factor modem into reality.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 More specifically, we would do the design at the schematics+BOM level while the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 the PCB layout step would have to be outsourced at cost.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
24 Approach 2 (NOT preferred, but can sometimes be agreed to in limited cases):
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 someone else does the repackaging work under their own control.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27 In the case of Approach 1 the new modem product will always be guaranteed to
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 work flawlessly and be fully compatible with our FreeCalypso sw and fw
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 architecture because in this case the hardware design is personally supervised
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30 by the Mother of FreeCalypso and must receive her approval prior to being
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31 released to layout and then to fabrication. In the case of Approach 2 this
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32 assurance is lacking. This document provides some technical guidelines that
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 MUST be followed in order for a new modem hw product to stand a chance at being
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
34 compatible with FreeCalypso; anyone who follows Approach 2 against our
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
35 recommendation but still wishes to have a chance at receiving support from us
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
36 MUST follow these design guidelines.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
37
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
38 LEGAL NOTICE: Following these technical guidelines does NOT by itself grant you
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
39 a license to use our FreeCalypso trademark on your hardware products; this
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
40 trademark is personally owned by Mychaela N. Falconia and only she has the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
41 authority to license its use at her sole discretion. Similarly our agreement
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
42 with GSMA does NOT allow us to sublet any part of our IMEI number range to any
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
43 other parties; any IMEI number ranges that may be allocated by GSMA to
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
44 FreeCalypso products may ONLY be used for those products that are physically
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
45 produced by Falconia Partners LLC from start to finish and not any others.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
46
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
47 Basic technical guidelines
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
48 ==========================
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
49
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
50 The purpose of these guidelines is to make it possible for the same firmware
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
51 build configuration to support both our existing FCDEV3B and various
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
52 repackagings of the underlying core modem solution (FC-TMS), i.e., to have the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
53 same official FC Magnetite firmware builds for target fcdev3b run not only on
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
54 the original development board, but on all physical repackagings of the same
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
55 core modem solution. To make such firmware reuse possible, the following
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
56 hardware design constraints MUST be followed:
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
57
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
58 * The flash+RAM chip must be the same Spansion S71PL129NC0HFW4B as used on our
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
59 FCDEV3B, and it must be wired the same way: first flash chip select on Calypso
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
60 nCS0, RAM on nCS1, second flash chip select on nCS2. The flash reset line
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
61 needs to be wired the same way as on FCDEV3B V2, otherwise Calypso sleep modes
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
62 will be broken. We realize that this flash and RAM capacity (16 MiB and
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
63 8 MiB, respectively) is extreme overkill for typical modem applications
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
64 outside of development, but supporting multiple flash chip types would
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
65 introduce a configuration management burden which we are not willing to
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
66 take on.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
67
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
68 * Calypso's unused DSR_MODEM/LPG pin was left unconnected in Openmoko's version
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
69 but on our FCDEV3B it is tied to GND on the board. Other boards seeking to
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
70 be FreeCalypso-compatible need to have this pin tied to GND as well because
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
71 our firmware leaves this pin in its default power-up config of DSR_MODEM input
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
72 and does not change it to LPG output - leaving it unconnected would cause it
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
73 to float.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
74
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
75 * Our firmware configures Calypso GPIO 3 as an input; GPIOs 0-2 and those
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
76 multifunction pins which are unused and configured as GPIOs (TSPDI/IO4,
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
77 BCLKX/IO6, MCUEN1/IO8 and MCUEN2/IO13) are configured as outputs. Board
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
78 wiring must be compatible with these directions: those pins which our fw
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
79 drives as outputs can be simply left unconnected, while GPIO 3 needs to be
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
80 sensibly driven or tied off as explained below.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
81
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
82 * If someone needs a modem that produces an Openmoko-style application processor
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
83 wakeup signal (asserted by the fw when the modem needs to send something to
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
84 the host but is blocked by CTS being held high), this signal should be
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
85 connected to GPIO 0. Openmoko used GPIO 1 for this purpose, but in
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
86 FreeCalypso GPIO 1 is taken because we use it for the loudspeaker control
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
87 signal like on TI's D-Sample and Leonardo boards, hence we are moving the AP
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
88 wakeup signal to GPIO 0, to be implemented if and when anyone builds a modem
3
4f873ec004f6 FCDEV3B-repackaging: minor grammar fixes
Mychaela Falconia <falcon@freecalypso.org>
parents: 2
diff changeset
89 based on FC-TMS that needs to provide such a signal.
2
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
90
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
91 * If your product includes a loudspeaker amplifier like on our FCDEV3B, connect
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
92 its on/off control input to GPIO 1, otherwise leave our GPIO 1 output
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
93 unconnected.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
94
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
95 * Our fw produces a DCD modem control output on GPIO 2; if you are connecting
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
96 the MODEM UART channel to an RS-232 port or to a USB-serial chip with a full
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
97 set of modem control signals, connect DCD to GPIO 2.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
98
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
99 * Our fw treats GPIO 3 as a DTR modem control input following TI's C-Sample and
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
100 D-Sample boards. If your product has a real DTR signal coming from an RS-232
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
101 interface or from a USB-serial chip, connect it to GPIO 3, otherwise GPIO 3
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
102 needs to be pulled down to GND like on Leonardo and FCDEV3B.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
103
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
104 * If you are connecting the MODEM UART channel to a full RS-232 port or to a
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
105 USB-serial chip with a full set of modem control signals, you should connect
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
106 DSR and RI to TSPDI/IO4 and MCUEN1/IO8, respectively. Right now our fw
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
107 drives IO4 low and IO8 high, corresponding to DSR asserted and RI negated
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
108 (normal quiescent state), and connecting the signals in this way allows the
3
4f873ec004f6 FCDEV3B-repackaging: minor grammar fixes
Mychaela Falconia <falcon@freecalypso.org>
parents: 2
diff changeset
109 possibility of extending the fw to drive them in some more intelligent manner
4f873ec004f6 FCDEV3B-repackaging: minor grammar fixes
Mychaela Falconia <falcon@freecalypso.org>
parents: 2
diff changeset
110 if need be.
2
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
111
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
112 * Both Calypso UARTs need to be wired in an accessible way so that our standard
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
113 FC Magnetite firmware can be used with the AT command interface on the MODEM
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
114 UART and RVTMUX on the IrDA UART.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
115
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
116 * Our fw configures the MODEM UART with hardware flow control enabled; if your
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
117 applications lacks RTS/CTS signals, then Calypso's CTS_MODEM signal needs to
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
118 be pulled down to GND so it is seen as asserted.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
119
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
120 * Our fw configures the 4 MCSI/GPIO pins as MCSI rather than GPIO. If your
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
121 board does not use MCSI because you are tapping VSP instead or not using any
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
122 digital voice interface at all, then you should put pull-down resistors on
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
123 MCSI_RXD, MCSI_CLK and MCSI_FSYNCH, otherwise these signals will float.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
124
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
125 Tapping VSP for the digital voice interface
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
126 ===========================================
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
127
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
128 The Calypso+Iota chipset includes an interface called VSP for Voice Serial Port;
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
129 per TI's design intent it is a strictly private interface between Calypso and
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
130 Iota chips, but it is possible to tap into this interface to get an external
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
131 digital voice channel. TI's official method for getting a digital voice channel
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
132 out of a Calypso modem is to use MCSI in their so-called "Bluetooth headset"
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
133 mode, however, our experiments on the FCDEV3B have revealed that this interface
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
134 does not work the way one would naively expect. Unless we can convince TI to
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
135 dig up and release the sources for the Calypso DSP ROM, which we obviously
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
136 cannot count on, we won't be able to use MCSI reliably until and unless we
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
137 undertake to fully reverse their DSP ROM code from disassembly, which would be
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
138 an extremely major and very costly undertaking. Because of this unfortunate
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
139 situation, the alternative way of tapping into VSP needs to be given
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
140 consideration.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
141
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
142 Tapping into VSP is absolutely not possible on our current FCDEV3B, as the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
143 signals in question are currently routed directly from one BGA to another and
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
144 do not come up to the surface at any accessible point. The same situation holds
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
145 on every other existing Calypso phone and modem known to us - after all, VSP was
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
146 meant to be a private chip-to-chip interface. Instead we are presenting the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
147 idea of tapping VSP as a possibility for anyone who undertakes to repackage our
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
148 FC-TMS into some new form factor and desires a digital voice channel while at
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
149 it.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
150
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
151 In TI's standard solution VSP clock and frame sync signals are generated by the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
152 Iota ABB and are inputs to the Calypso DBB. Because they are inputs to the
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
153 Calypso, it may be tempting to disconnect them from the ABB and have them
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
154 originate from an external source instead - however, TI's DSP code in the ROM
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
155 was most certainly written with the assumption that these signals will only
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
156 ever be driven by their ABB and never by anyone else, hence having them come
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
157 from a source whose timing does not come from the Calypso can cause all kinds
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
158 of strangeness which we will never be able to debug properly because the DSP is
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
159 a mysterious black box. Therefore, my (Mother Mychaela's) stance is that if
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
160 you break the VSP connection between Calypso and Iota, then you are entirely on
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
161 your own - don't expect any help from me. Instead my idea is to tap into VSP
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
162 without breaking it, specifically:
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
163
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
164 * Keep the clock and frame sync connection between Calypso and Iota, with Iota
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
165 remaining the driver on these nets - but also bring these signals out
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
166 externally, so external logic can sync itself to this interface as well.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
167
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
168 * Do likewise for the line that carries downlink voice from the DBB to the ABB:
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
169 let the ABB receive it and use it to drive the analogue earpiece output (which
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
170 would be unconnected in a digital voice application), but let external logic
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
171 receive it too.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
172
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
173 * Break only the line that carries uplink voice from the ABB to the DBB: bring
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
174 the Iota output side on one external interface pin and the Calypso input side
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
175 on another external interface pin. Putting a jumper on these adjacent header
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
176 pins would restore TI's original configuration and allow uplink voice to come
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
177 from an analogue microphone connected to the ABB, and if a digital uplink
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
178 voice source is desired, remove the jumper and have an external source provide
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
179 the bits which would otherwise come from Iota's voice ADC.
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
180
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
181 The above approach would provide a usable digital voice interface that would be
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
182 completely transparent (invisible) to the Calypso DSP and even to the ARM-side
020df28341d0 FCDEV3B-repackaging article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
183 firmware, hence it should work without any nasty surprises.
4
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
184
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
185 Triband vs. quadband
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
186 ====================
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
187
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
188 One shortcoming of our current FreeCalypso modem solution is that it is triband
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
189 and not quadband; more specifically our standard hw build omits the GSM850 band,
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
190 or we can build a different configuration that supports GSM850 but omits EGSM
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
191 (the 900 MHz band). To the best of our knowledge the GSM850 band is used very
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
192 little these days, but being only triband makes us look bad compared to the
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
193 competition: all of the mainstream proprietary GSM modem modules are fully
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
194 quadband these days.
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
195
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
196 It *is* possible to make a Calypso-based quadband modem, as TI had one: their
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
197 Leonardo reference board for the Calypso+Iota+Rita chipset existed in several
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
198 versions some of which were quadband, and their E-Sample board (Calypso+) which
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
199 used the same Rita RF block was also quadband. However, changing our current
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
200 FC modem design from triband to quadband would involve a highly invasive PCB
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
201 layout change: basically our entire modem PCB layout and particularly the GHz RF
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
202 section would have to be ripped up and reshuffled into a different arrangement.
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
203 Furthermore, if we as the FreeCalypso community do decide that we wish to
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
204 produce a quadband modem, I (Mother Mychaela) would NOT be comfortable with
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
205 entrusting the needed re-layout work to an "ordinary" PCB layout contractor who
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
206 is not a cellphone RF design expert, instead we would need to get a consultation
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
207 from an RF PCB design expert who has experience very specifically with GSM
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
208 cellphone design and not any other applications. Finding such an expert would
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
209 be a major task in itself, and that expert most certainly won't come cheap.
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
210 Therefore, a quadband FreeCalypso modem probably won't happen unless we get
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
211 someone with a lot of money to throw around.
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
212
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
213 There is one exception, though: if anyone would like to see our FreeCalypso
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
214 modem repackaged into the SMT module form factor copied from BenQ M32 and pays
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
215 for that venture, the result would be naturally quadband as the layout of BenQ's
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
216 module follows the same floorplan in the RF section as TI's quadband Leonardo
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
217 and E-Sample layout. However, that approach would involve a step to reverse-
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
218 engineer BenQ's layout by slicing their board and imaging its inner layers,
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
219 hence anyone seeking this approach would need to be prepared to pay for that
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
220 step.
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
221
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
222 If anyone ever does pay for the creation of a quadband version of our
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
223 FreeCalypso modem solution, be it in BenQ's physical form factor or some other,
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
224 this quadband modem will need a different firmware build configuration: there
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
225 is no way to have the same fw image work on both triband and quadband modems
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
226 given that the RFFE control signals are different, and there would be no way for
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
227 the fw to autodetect which hw it is running on. But all of the other design
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
228 guidelines listed above should still be followed, so we can have only two fw
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
229 build configurations (triband and quadband) without an explosion of further
1dbc8c5d9698 FCDEV3B-repackaging: triband vs. quadband section added
Mychaela Falconia <falcon@freecalypso.org>
parents: 3
diff changeset
230 build variants for different GPIO wiring and whatnot.