SmartBoard Baseboard v1.01

See the SmartBoard Baseboard main page for top-level details.

Detailed Guide - Excerpts

A detailed guide is available with the PCB. Here are Detailed Guide - Excerpts.

Construction Notes

For ease of construction, follow these steps - in the order listed here.

1. Install topside SMD diodes (if you need them). The bottom side go on later.
   • D2,D4 and D6
2. Install microSD holder SD1.
   • Example carefully to make sure there are no solder shorts between leads.
3. Install Battery Holder as follows:
   • First, apply solder to the pad centered under the battery holder, then clean off most of it leaving a smooth surface. This creates just enough of a raised 'pad' for the battery to make good contact.
   • Second, install the battery holder BAT1.
   • DO NOT install the battery.
4. Install the ICs
   • IC3,4 for the CAN interface (or sockets if you may experiment with different chips)
   • IC5 for RS-232 (if needed)
5. Install the socket for the mbed (tack the 4 corners and temporarily install the mbed to check alignment before solding all the pins).
6. Install the screw terminal connectors at the left, front and right board edge
   • X1 for Analog
   • X2 for SPI1
   • X4,5 for either Serial2 or I2C2 (if not using X6 for the DB-9)
   • X8,7 for CAN1,2 (which also serve as the primary Power connection)
     • Resist the temptation to join X7 and X8 before insertion. The PCB hole spacing prevents them from being joined and then inserted.
7. Install all of the passives. Be sure the right part goes in the right location.
   • Rs
   • Cs
8. Install USB/Ethernet connector
9. Install DB9 (if you didn't install X4,X5)
10. Install remaining components
    • PWM Connectors PW1,2,3,4,5 and 6
    • Headers for Jumpers JP1,2,3,4,5,6,8,10,11,12
11. Install bottom side SMD diodes (if you need them)
    • D3,D5 and D7

Designators not used:

• JP7, JP9

First Power Up

• Do not yet install the mbed module.
• Set power supply to very low current limit (10 mA) and power up at 7v (applied to pin 1, 2 of CAN connector).
• Measure around the board to check for proper voltages. If you have a short somewhere the power supply will not be working properly. Ensure the voltage regulator is outputting 5v.
• Power off.
• Install mbed.
• Power up (you will need to increase the current limit if you have such a supply).
• Measure voltages around the board again.
• Install the SmartBoard Hardware Tester to verify most of the circuits.
  • Serial communications via the USB port on the mbed module controls and outputs the results. Set your PC serial program to 921,600 baud.
  • If CAN is installed, wire channel 1 to channel 2
    • If you did not install R3 or R5, connect one of them between CAN-H and CAN-L at the connector.
  • Plug in Ethernet to enable network access.
  • Plug in a micro SD card to check that port.
  • Plug in a USB memory stick to check that port.

Smartboard Hardware Tester

After installing the test application, and restarting the mbed, you should see the following on your serial communications program. If you strike a key early in the startup process, it will pause at the menu, awaiting your command. If you do not, it will start automatically running the tests. In the sample below, I struck '?' at startup.

SmartBoard Hardware Tester [Mar 31 2011 11:08:25]
  SmartBoard Hardware                    v0.05
  SmartBoard Software                    v0.13

                      [USB]       [Eth/USB]
 +---------------+------------+---+-------+---+
 |O [RS232 1-2]  |  |       | |   |       |  O|
 |               |  |microSD| |   |       |   |
 |S              |  |       | |   |       |  C|
 |P              |  +-------+ |   |       |  A|
 |I              |            |   |Yl   Gr|  N|
 |1              |            |   +-------+  1|
 |-              |            |              -|
 |2              |     RTC    |              2|
 |               |  (Battery) |               |
 |               |            |               |
 |               | 1  2  3  4 |               |
 |               +------------+               |
 |O[Analog In ]        O        [PWM Out]    O|
 +--------------------------------------------+

> ?
Commands:
  L   LED_Tests();          // Blink each in turn
  P   PWM_Tests();          // Ramps the PWM channels
  A   AnalogIn_Tests();     // Measures voltage on each
  R   RTC_Tests();          // Saves current time, alters it, restores it
  M   MicroSD_Tests();      // Writes and Reads file on an installed card
  S   RS_232_Tests();       // Outputs simple text
  C   CAN_Tests();          // Requires CAN1 wired to CAN2, loops messages
  E   Ethernet_Tests();     // Sets the clock from a time server
  U   USBHost_Tests();      // Writes and Reads file on a memory stick
  F   FileSystems_Tests();  // Writes and Reads file on internal file system
  X   eXit to automatic testing
>

Design

The schematic, pcb layout, BOM and design notes are on the main SmartBoard page, and incorporated into the design were the suggestions of several mbed users.