FreeCalypso > hg > freecalypso-docs

annotate DUART-cable @ 32:78c2cc6ebbb8

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
DUART-cable: update for DUART28
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 24 Sep 2020 02:47:14 +0000
parents f7ed8c45a8ec
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
32
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
1 2020-09 update: we have now produced our own DUART28 adapter that takes the
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
2 place of PLDkit FT2232D breakout boards. The article that follows was written
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
3 in 2019-12, before our DUART28 was even conceived, and it was written for
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
4 PLDkit FT2232D adapters. The new cable that needs to be used with DUART28 is
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
5 different: DUART28 brings out a 10-pin header in the same pinout as our Calypso
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
6 boards, thus the connection between the two boards becomes a straight-through
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
7 10-wire ribbon cable.
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
8
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
9 Original 2019-12 article follows
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
10 ================================
78c2cc6ebbb8 DUART-cable: update for DUART28
Mychaela Falconia <falcon@freecalypso.org>
parents: 27
diff changeset
11
27
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 The Calypso chip has two UARTs, called MODEM and IrDA in the chip docs. The
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 primary UART (MODEM) has 4 signals (TxD, RxD, RTS and CTS), whereas the other
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 UART (IrDA) has data leads only (TxD and RxD). TI's C-Sample and D-Sample
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 boards have also established a convention whereby Calypso GPIOs 2 and 3 have
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 been assigned as supplementary modem control signals for the primary MODEM UART,
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 with GPIO 2 being an output from Calypso signaling DCD to the host and with
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 GPIO 3 being an input to Calypso receiving DTR from the host. Note that DSR
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 and RI are still missing in this arrangement.
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 In FreeCalypso we have further established our own convention: all FC hardware
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 products that bring out both Calypso UARTs do so by way of a single 10-pin (2x5)
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23 2.54 mm header in a fixed pinout given below. This convention was started with
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
24 FCDEV3B, our first FC hw product, and is now being continued with MMTB1 and
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 other boards. Our standardized DUART header pinout is as follows:
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27 Header pin Calypso signal
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 1 GND
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 2 GND
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30 3 TX_IRDA
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31 4 TX_MODEM
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32 5 RX_IRDA
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 6 RX_MODEM
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
34 7 GPIO2_DCD
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
35 8 RTS_MODEM
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
36 9 GPIO3_DTR
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
37 10 CTS_MODEM
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
38
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
39 Pins 7 and 9 were originally left unused (they are unconnected on FCDEV3B), but
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
40 they have been assigned as DCD and DTR (from the host's perspective) starting
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
41 with MMTB1. Note that while DCD and DTR in the table above are named from the
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
42 host's perspective, all Calypso signals ending with _MODEM or _IRDA are from
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
43 the chip's perspective, i.e., the opposite.
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
44
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
45 Our standard recommended practice for connecting to our two UARTs from a regular
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
46 PC or laptop is to use FT2232D breakout boards from the following vendor:
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
47
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
48 http://pldkit.com/other/ft2232d-module
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
49
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
50 FT2232D is a versatile USB-to-various-things adapter, but in its default
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
51 configuration which we use here it acts as a bridge from USB to two UARTs,
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
52 presenting both UARTs behind a single USB device. The breakout board made and
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
53 sold by PLDkit has two rows of header pins, featuring 15 pins on each side, and
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
54 the two sides of the board neatly correspond to the A and B sides of FT2232D.
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
55
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
56 Our standard recommended method for connecting our two UARTs to a PLDkit FT2232D
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
57 board is to use a 10-wire ribbon cable that is custom-assembled as follows:
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
58
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
59 * One end is terminated with a 10-pin female connector that mates with the DUART
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
60 header on our modem boards;
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
61
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
62 * The other end is split into two parts as described below, and each split end
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
63 is terminated with a 15-pin female connector that mates with one side of the
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
64 FT2232D breakout board.
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
65
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
66 The split between A and B sides on the FT2232D end is not symmetric, instead 7
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
67 wires go to side A for the MODEM UART and 3 wires go to side B for the IrDA
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
68 UART. Assuming the standard color code, the 10-wire ribbon cable gets split
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
69 between violet and grey wires: brown to violet go to side A, grey to black go
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
70 to side B. After each wire has been stripped and fitted with a crimp-on female
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
71 terminal, FT2232D side A wires need to be inserted into the connector housing
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
72 as follows:
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
73
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
74 Wire Pin position FT2232D signal UART signal (host perspective)
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
75 brown 2 ADBUS0 TxD
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
76 red 3 ADBUS1 RxD
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
77 orange 4 ADBUS2 RTS
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
78 yellow 5 ADBUS3 CTS
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
79 green 6 ADBUS4 DTR
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
80 blue 8 ADBUS6 DCD
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
81 violet 15 GND GND
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
82
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
83 FT2232D side B wires need to be inserted into the other connector housing as
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
84 follows:
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
85
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
86 Wire Pin position FT2232D signal UART signal (host perspective)
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
87 grey 2 BDBUS0 TxD
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
88 white 3 BDBUS1 RxD
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
89 black 15 GND GND
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
90
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
91 The wires on the other end of the cable (also stripped and fitted with crimp-on
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
92 female terminals) need to be inserted into another connector housing that will
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
93 mate with the DUART connector on FreeCalypso modem boards; the pin assignment
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
94 is as follows:
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
95
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
96 Pin position Calypso signal Wire
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
97 1 GND black
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
98 2 GND violet
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
99 3 TX_IRDA white
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
100 4 TX_MODEM red
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
101 5 RX_IRDA grey
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
102 6 RX_MODEM brown
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
103 7 GPIO2_DCD blue
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
104 8 RTS_MODEM yellow
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
105 9 GPIO3_DTR green
f7ed8c45a8ec DUART-cable article written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
106 10 CTS_MODEM orange