[challenge-bot] / pcb / index.html

								<HTML>
								<Head>
								<Title>
MBino (Rev. C)
								</Title>
								</Head>
								<Body>
								<H1>
MBino (Rev. C)
								</H1>
								<P>
								</P>
								<H2>
Table of Contents
								</H2>
								<P>
								<UL><LI>
	<A HRef="#Schematic">
    1.0 Schematic</A>
								</LI><LI>
	<A HRef="#Design_Files">
    2.0 Design Files</A>
								</LI><LI>
	<A HRef="#Errata_and_Notes">
    3.0 Errata and Notes</A>
								</LI><LI>
	<A HRef="#Bootloader">
    4.0 Bootloader</A>
								</LI><LI>
	<A HRef="#IDE">
    5.0 IDE</A>
								</LI></UL>
								</P>
								<H2>
    <A Name="Schematic">
1.0 Schematic</A>
								</H2>
								<P>
The schematic is available as either a
    <A HRef="busduino.pdf">
.pdf</A> file or as a
    <A HRef="busduino.svg">
.svg</A> (Scalable Vector Graphics) file.
The .pdf file should print reasonably well on a black
and white printer.  The .svg file is embedded below:
								</P>

    <Img Src="busduino.svg">
								<P>
There are two 2.1mm power jacks , N1 and N3.
N1 feeds power through protection diode D1 and
protection resettable polyfuse F2 to the LPWR1
and LWPR2 pins of MakeBus connector N2.  D1 protects
everthing if the power accidentally comes in with
reverse polarity on N1.  (Connector N2 is labeled as
"Robus" which is the previous bus name to "MakerBus".)
The ground line of N1 is also connected to LGND1
and LGND2 of N2.  The same thing happens with N3,
F1, and D2 with BPWR1, BPWR2, BGND1, and BGND2 on N2.
								</P><P>
The LPWR1 and LPWR1 lines from N2 are further connected
to the 5V linear regulator U1 and the 3.3V linear
regulator U2 to provide 5 volts and 3.3 volts respectively.
								</P><P>
CANH and CANL of N2 or connected to the 5V CAN bus
transceiver chip U3.  The 1 &times; 3 jumper J1 can
be jumpered to connect a 124 ohm termination resistor R6.
The 24K resistor R9 enables slope control for U3.
The TXD and RXD pins are connected to the microcontroller
U4 pins PD3 (TXD1) and PD2 (RXD1).  Capacitors C5-C10
are .1&micro;F bypass capacitors for U4 and U3.
16MHz crystal X1 and crystal 22pF capactiors C4 and C5
provide the 16MHz frequency reference for U4.
								</P><P>
Connector N4 is a 2&times;8 pin combined JTAG and
serial download connector that connects to the
various JTAG pins on the microcontroller (U4).
The serial debug lines from N4 are also connected
to the 1&times;6 serial cable pin N5 before
connecting to PD1 (TXD0) and PD0 (RXD0) on U4
through 1K ohm resistors R2 and R3.  R2 and R3
pins D0 (N9) and D1 (N9) to have priority over
over both N4 and N5 is voltage sources are connected
to both at the same time.  It is a really bad idea
to attempt to use both N4 and N5 for serial downloading
at the same time.  10K ohm resistor R1 and 1&micro;F
capacitor C12 provide a simple reset circuit to trigger
RESET on U4.  The reset button SW1 can also be used
to manually reset U4.
								</P><P>
470 Ohm resistor R8 and LED D4 are connected to D13
(N8) to provide an on-board LED.  470 ohm resistor R7
and bicolor LED D3 are only meant to be used for
debugging; they are not installed in the final product.
Connectors N6 (Power/Reset pins), N7 (ISP header),
N8 (D0-D13, GND, AREF), N9 (D0-D7) and N10 (A0-A5)
are used used to connect to Arduino compatible shields.
								</P><P>
4.7K ohm resistors R4 and R5 are available to be used
as pull up resistors for the I<Sup>2</Sup>C bus pins
connected to D13 (SCK) and D12 (MISO) pins on U4.
								</P>
								<H2>
    <A Name="Design_Files">
2.0 Design Files</A>
								</H2>
								<P>
This board was designed using KiCAD.  A complete KiCAD
archive of board is found in
    <A HRef="busduino.zip">
busduino.zip</A>.  ("BusDuino" was the original name
of the board before it was renamed to "MBino".)
When this file is unzipped, the KiCad project file
can be found down in
<Code>robus/busdino/rev_b/busdino.pro</Code>.  Various
shared <Code>.mod</Code> and <Code>.lib</Code> files
are kept in the <Code>robus</Code> directory.  All
Gerber and drill files are generated using KiCad.
								</P>
								<H2>
    <A Name="Errata_and_Notes">
3.0 Errata and Notes</A>
								</H2>
								<P>
The following errors and issues are noted:
								<UL><LI>
    U1 Vin/Vout pins are swapped
								</LI><LI>
    A reset circuit from MakerBus is needed.
								</LI></UL>
								</P><P>
The design notes for the reset circuit are:
								<UL><LI>
Use a SNLVC2G06 (dual open collector inverter):
								</LI><LI>
At VCC = 5V:
								<UL><LI>
   V<Sub>IH</Sub> = .7 * V<Sub>CC</Sub> = 3.5V
								</LI><LI>
   V<Sub>IL</Sub> = .3 * V<Sub>CC</Sub> = 1.5V
								</LI><LI>
   V<Sub>OL</Sub> = .55V
								</LI><LI>
   I<Sub>OL</Sub> = 32mA
								</LI></UL>
								</LI><LI>
Assuming that the capacitor is clamped to VOL most
of the time, the R*C that corresponds to charging
from VOL to VIH in T seconds is the
the basic capacitor charging equation:
								</LI><UL><LI>
  V(t) = V<Sub>OL</Sub> + (V<Sub>CC</Sub> -
     V<Sub>OL</Sub>) * (1 - e<Sup>-t/R*C</Sup>)
								</LI></UL><LI>
Replacing V(t) with V<Sub>IH</Sub> and T:
								<UL><LI>
  V<Sub>IH</Sub> = V<Sub>OL</Sub> + (V<Sub>CC</Sub> -
    V<Sub>OL</Sub>) * (1 - e<Sup>-T/R*C</Sup>)
								</LI></UL>
								</LI><LI>
Solving for RC:
								<UL><LI>
  (V<Sub>IH</Sub> - V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>L</Sub>) = 
  1 - e<Sup>-T/R*C</Sup>
								</LI><LI>
  e<Sup>-T/R*C</Sup> = 1 - (V<Sub>IH</Sub> -
    V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>OL</Sub>)
								</LI><LI>
  -T/R*C = ln(1 - (V<Sub>IH</Sub> -
    V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>OL</Sub>))
								</LI><LI>
  R*C = -T/ln(1 - (V<Sub>IH</Sub> -
    V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>OL</Sub>))
								</LI></UL>
								</LI><LI>
Substituting in for T=1mS, V<Sub>IH</Sub>,
V<Sub>OL</Sub>, and V<Sub>CC</Sub>:
								<UL><LI>
  R*C =  -.001/ln(1 - (3.5 - .55)/(5 - .55))
								</LI><LI>
  R*C = -.001/-1.08744
								</LI><LI>
  R*C = .009196
								</LI></UL>
								</LI><LI>
Setting C = .1&micro;F
								<UL><LI>
  R = .009196 / .0000001 = 9196
								</LI></UL>
Using an R near 10K should do the trick.
								</LI><LI>
The maximum discharge current is I<Sub>OL</Sub>.  Use Ohm's law
to determine determine discharge resistor:
								<UL><LI>
   V = I * R
								</LI><LI>
   R = V / I
     = 5 / .032
     = 156.25
								</LI></UL>
Setting R<Sub>discharge</Sub> = 180 should be good enough.
								</LI><LI>
The charge/discharge ratio is:
								<UL><LI>
  R<Sub>charge</Sub>/R<Sub>discharge</Sub> = 10K/180 = 55.5
								</LI></UL>
								</LI></UL>
								<P>
								<H2>
    <A Name="Bootloader">
4.0 Bootloader</A>
								</H2>
								<P>
{Bootloader discussion goes here!}
								</P>
								<H2>
    <A Name="IDE">
5.0 IDE</A>							</H2>
								<P>
The following URL specifies how to add a new board:
								<BlockQuote>

	<A HRef="http://www.avr-developers.com/corefiles/index.html">
    http://www.avr-developers.com/corefiles/index.html</A>
								</BlockQuote>
								</P><P>
The short answer is:
								<Pre>
    cd .../hardware
    (cd arduino; tar cvf /tmp/arduino.tar .)
    (mkdir {your_board_dir}; tar xvf /tmp/arduino.tar)
    # now edit {your_board_dir}/boards.txt to configure your board
    # now edit {your_board_dir}/programmers.txt
								</Pre>
The problem with this strategy is that you get a snap-shot of
all the files and everything becomes out of date when the next
release of the Arduino IDE comes out.  A better way is probably
to have a shell script that make a copy of arduino files followed
by a file that unzips the stuff that needs to be changed.  That
may be just a few files.
								</P><P>
Here are the files that have been edited so far:
								<DL><DT>
  .../MBino/variants/standard/pins_arduino.h:			</DT><DD>
								<Pre>
    // Add 4 pins to the vector for I2C SDA, SCL, and external pull-ups
    SDA = 20
    SCL = 21

    port_to_mode_PGM = {
	// Add &DDRA,	// ATmega324 has a Port A

    port_to_output_PGM = {
	// Add &PORTA,	// ATmega324 has a Port A

    port_to_input_PGM = {
	// Add &PINA,	// ATmega324 has a Port A

    digital_pin_to_port_PGM = {
	// Remap digital pin ports

    digital_pin_to_bit_mask_PGM = {
	// Remap bit masks
								</Pre>
Obviously thes is pretty minor changes.
								</DD></DL>
								</P><P>
{Create a .zip file that creates the various MBino
sub-directories for the Arduino IDE.}
								</P>
								<HR>
								<Address>
    <A HRef="http://gramlich.net/copyright.html">
Copyright</A> 2013 by
    <A HRef="http://gramlich.net/index.html">
Wayne C. Gramlich</A>.
All rights reserved.
								</Address>
								</Body>
								</HTML>
Commit	Line	Data
468dbff9 WG	1	<HTML>
	2	<Head>
	3	<Title>
	4	MBino (Rev. C)
	5	</Title>
	6	</Head>
	7	<Body>
	8	<H1>
	9	MBino (Rev. C)
	10	</H1>
	11	<P>
	12	</P>
	13	<H2>
	14	Table of Contents
	15	</H2>
	16	<P>
	17	<UL><LI>
	18	<A HRef="#Schematic">
	19	1.0 Schematic</A>
	20	</LI><LI>
	21	<A HRef="#Design_Files">
	22	2.0 Design Files</A>
	23	</LI><LI>
	24	<A HRef="#Errata_and_Notes">
	25	3.0 Errata and Notes</A>
	26	</LI><LI>
	27	<A HRef="#Bootloader">
	28	4.0 Bootloader</A>
	29	</LI><LI>
	30	<A HRef="#IDE">
	31	5.0 IDE</A>
	32	</LI></UL>
	33	</P>
	34	<H2>
	35	<A Name="Schematic">
	36	1.0 Schematic</A>
	37	</H2>
	38	<P>
	39	The schematic is available as either a
	40	<A HRef="busduino.pdf">
	41	.pdf</A> file or as a
	42	<A HRef="busduino.svg">
	43	.svg</A> (Scalable Vector Graphics) file.
	44	The .pdf file should print reasonably well on a black
	45	and white printer. The .svg file is embedded below:
	46	</P>
	47
	48	<Img Src="busduino.svg">
	49	<P>
	50	There are two 2.1mm power jacks , N1 and N3.
	51	N1 feeds power through protection diode D1 and
	52	protection resettable polyfuse F2 to the LPWR1
	53	and LWPR2 pins of MakeBus connector N2. D1 protects
	54	everthing if the power accidentally comes in with
	55	reverse polarity on N1. (Connector N2 is labeled as
	56	"Robus" which is the previous bus name to "MakerBus".)
	57	The ground line of N1 is also connected to LGND1
	58	and LGND2 of N2. The same thing happens with N3,
	59	F1, and D2 with BPWR1, BPWR2, BGND1, and BGND2 on N2.
	60	</P><P>
	61	The LPWR1 and LPWR1 lines from N2 are further connected
	62	to the 5V linear regulator U1 and the 3.3V linear
	63	regulator U2 to provide 5 volts and 3.3 volts respectively.
	64	</P><P>
65	CANH and CANL of N2 or connected to the 5V CAN bus
66	transceiver chip U3. The 1 × 3 jumper J1 can
67	be jumpered to connect a 124 ohm termination resistor R6.
68	The 24K resistor R9 enables slope control for U3.
69	The TXD and RXD pins are connected to the microcontroller
70	U4 pins PD3 (TXD1) and PD2 (RXD1). Capacitors C5-C10
71	are .1µF bypass capacitors for U4 and U3.
72	16MHz crystal X1 and crystal 22pF capactiors C4 and C5
73	provide the 16MHz frequency reference for U4.
74	</P><P>
75	Connector N4 is a 2×8 pin combined JTAG and
76	serial download connector that connects to the
77	various JTAG pins on the microcontroller (U4).
78	The serial debug lines from N4 are also connected
79	to the 1×6 serial cable pin N5 before
80	connecting to PD1 (TXD0) and PD0 (RXD0) on U4
81	through 1K ohm resistors R2 and R3. R2 and R3
82	pins D0 (N9) and D1 (N9) to have priority over
83	over both N4 and N5 is voltage sources are connected
84	to both at the same time. It is a really bad idea
85	to attempt to use both N4 and N5 for serial downloading
86	at the same time. 10K ohm resistor R1 and 1µF
87	capacitor C12 provide a simple reset circuit to trigger
88	RESET on U4. The reset button SW1 can also be used
89	to manually reset U4.
90	</P><P>
91	470 Ohm resistor R8 and LED D4 are connected to D13
92	(N8) to provide an on-board LED. 470 ohm resistor R7
93	and bicolor LED D3 are only meant to be used for
94	debugging; they are not installed in the final product.
95	Connectors N6 (Power/Reset pins), N7 (ISP header),
96	N8 (D0-D13, GND, AREF), N9 (D0-D7) and N10 (A0-A5)
97	are used used to connect to Arduino compatible shields.
98	</P><P>
99	4.7K ohm resistors R4 and R5 are available to be used
100	as pull up resistors for the I<Sup>2</Sup>C bus pins
101	connected to D13 (SCK) and D12 (MISO) pins on U4.
102	</P>
103	<H2>
104	<A Name="Design_Files">
105	2.0 Design Files</A>
106	</H2>
107	<P>
108	This board was designed using KiCAD. A complete KiCAD
109	archive of board is found in
110	<A HRef="busduino.zip">
111	busduino.zip</A>. ("BusDuino" was the original name
112	of the board before it was renamed to "MBino".)
113	When this file is unzipped, the KiCad project file
114	can be found down in
115	<Code>robus/busdino/rev_b/busdino.pro</Code>. Various
116	shared <Code>.mod</Code> and <Code>.lib</Code> files
117	are kept in the <Code>robus</Code> directory. All
118	Gerber and drill files are generated using KiCad.
119	</P>
120	<H2>
121	<A Name="Errata_and_Notes">
122	3.0 Errata and Notes</A>
123	</H2>
124	<P>
125	The following errors and issues are noted:
126	<UL><LI>
127	U1 Vin/Vout pins are swapped
128	</LI><LI>
129	A reset circuit from MakerBus is needed.
130	</LI></UL>
131	</P><P>
132	The design notes for the reset circuit are:
133	<UL><LI>
134	Use a SNLVC2G06 (dual open collector inverter):
135	</LI><LI>
136	At VCC = 5V:
137	<UL><LI>
138	V<Sub>IH</Sub> = .7 * V<Sub>CC</Sub> = 3.5V
139	</LI><LI>
140	V<Sub>IL</Sub> = .3 * V<Sub>CC</Sub> = 1.5V
141	</LI><LI>
142	V<Sub>OL</Sub> = .55V
143	</LI><LI>
144	I<Sub>OL</Sub> = 32mA
145	</LI></UL>
146	</LI><LI>
147	Assuming that the capacitor is clamped to VOL most
148	of the time, the R*C that corresponds to charging
149	from VOL to VIH in T seconds is the
150	the basic capacitor charging equation:
151	</LI><UL><LI>
152	V(t) = V<Sub>OL</Sub> + (V<Sub>CC</Sub> -
153	V<Sub>OL</Sub>) * (1 - e<Sup>-t/R*C</Sup>)
154	</LI></UL><LI>
155	Replacing V(t) with V<Sub>IH</Sub> and T:
156	<UL><LI>
157	V<Sub>IH</Sub> = V<Sub>OL</Sub> + (V<Sub>CC</Sub> -
158	V<Sub>OL</Sub>) * (1 - e<Sup>-T/R*C</Sup>)
159	</LI></UL>
160	</LI><LI>
161	Solving for RC:
162	<UL><LI>
163	(V<Sub>IH</Sub> - V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>L</Sub>) =
164	1 - e<Sup>-T/R*C</Sup>
165	</LI><LI>
166	e<Sup>-T/R*C</Sup> = 1 - (V<Sub>IH</Sub> -
167	V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>OL</Sub>)
168	</LI><LI>
169	-T/R*C = ln(1 - (V<Sub>IH</Sub> -
170	V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>OL</Sub>))
171	</LI><LI>
172	R*C = -T/ln(1 - (V<Sub>IH</Sub> -
173	V<Sub>OL</Sub>)/(V<Sub>CC</Sub> - V<Sub>OL</Sub>))
174	</LI></UL>
175	</LI><LI>
176	Substituting in for T=1mS, V<Sub>IH</Sub>,
177	V<Sub>OL</Sub>, and V<Sub>CC</Sub>:
178	<UL><LI>
179	R*C = -.001/ln(1 - (3.5 - .55)/(5 - .55))
180	</LI><LI>
181	R*C = -.001/-1.08744
182	</LI><LI>
183	R*C = .009196
184	</LI></UL>
185	</LI><LI>
186	Setting C = .1µF
187	<UL><LI>
188	R = .009196 / .0000001 = 9196
189	</LI></UL>
190	Using an R near 10K should do the trick.
191	</LI><LI>
192	The maximum discharge current is I<Sub>OL</Sub>. Use Ohm's law
193	to determine determine discharge resistor:
194	<UL><LI>
195	V = I * R
196	</LI><LI>
197	R = V / I
198	= 5 / .032
199	= 156.25
200	</LI></UL>
201	Setting R<Sub>discharge</Sub> = 180 should be good enough.
202	</LI><LI>
203	The charge/discharge ratio is:
204	<UL><LI>
205	R<Sub>charge</Sub>/R<Sub>discharge</Sub> = 10K/180 = 55.5
206	</LI></UL>
207	</LI></UL>
208	<P>
209	<H2>
210	<A Name="Bootloader">
211	4.0 Bootloader</A>
212	</H2>
213	<P>
214	{Bootloader discussion goes here!}
215	</P>
216	<H2>
217	<A Name="IDE">
218	5.0 IDE</A> </H2>
219	<P>
220	The following URL specifies how to add a new board:
221	<BlockQuote>
222
223	<A HRef="http://www.avr-developers.com/corefiles/index.html">
224	http://www.avr-developers.com/corefiles/index.html</A>
225	</BlockQuote>
226	</P><P>
227	The short answer is:
228	<Pre>
229	cd .../hardware
230	(cd arduino; tar cvf /tmp/arduino.tar .)
231	(mkdir {your_board_dir}; tar xvf /tmp/arduino.tar)
232	# now edit {your_board_dir}/boards.txt to configure your board
233	# now edit {your_board_dir}/programmers.txt
234	</Pre>
235	The problem with this strategy is that you get a snap-shot of
236	all the files and everything becomes out of date when the next
237	release of the Arduino IDE comes out. A better way is probably
238	to have a shell script that make a copy of arduino files followed
239	by a file that unzips the stuff that needs to be changed. That
240	may be just a few files.
241	</P><P>
242	Here are the files that have been edited so far:
243	<DL><DT>
244	.../MBino/variants/standard/pins_arduino.h: </DT><DD>
245	<Pre>
246	// Add 4 pins to the vector for I2C SDA, SCL, and external pull-ups
247	SDA = 20
248	SCL = 21
249
250	port_to_mode_PGM = {
251	// Add &DDRA, // ATmega324 has a Port A
252
253	port_to_output_PGM = {
254	// Add &PORTA, // ATmega324 has a Port A
255
256	port_to_input_PGM = {
257	// Add &PINA, // ATmega324 has a Port A
258
259	digital_pin_to_port_PGM = {
260	// Remap digital pin ports
261
262	digital_pin_to_bit_mask_PGM = {
263	// Remap bit masks
264	</Pre>
265	Obviously thes is pretty minor changes.
266	</DD></DL>
267	</P><P>
268	{Create a .zip file that creates the various MBino
269	sub-directories for the Arduino IDE.}
270	</P>
271	<HR>
272	<Address>
273	<A HRef="http://gramlich.net/copyright.html">
274	Copyright</A> 2013 by
275	<A HRef="http://gramlich.net/index.html">
276	Wayne C. Gramlich</A>.
277	All rights reserved.
278	</Address>
279	</Body>
280	</HTML>