BV513-Mini
Please note for full instruction on this device see the instructions for the BV513 as this is simply a cut down version of that with minor changes to the socket layout.
The BV513-M is the same as the BV513 except the USB and SD-Card interface have been removed. The serial connection is now via a 10 pin connector. This is plug compatible with a BV101/2 or 3 on the 5V or 3.3V setting. The BV513-M comes without any connectors or the crystal for the RTC this is to give the maximum possible flexibility. If the RTC is not required and the crystal is installed this frees up two port pins, RC13 & RC14.
Socket Layout
The socket layout is slightly different to take into account that there is no on board 5V regulator, just a 3V3 regulator and so with the exception of 1 pin (JP8 pin 1) where there was a 5V o/p this is simply connected to pin 5 (V+) of the serial connector. In addition the no connection of JP3 pin 12 is now a 3V3 output.
Some of the markings on the current PCB are wrong, +5V should read +V as it is not known what voltage will be used to power the device and also pin 1 of JP8 is marked as +5V but this is in fact not connected to anything. The diagram below shows the correct power outputs.
Note on 3V3 Logic
Like the BV513 the PIC32 uses 3.3V logic, however the ports used for the serial interface is 5V tolerant and so will accept input from either the BV101 or BV102. It must be remembered though that the BV513-M will only output 0 and 3.3V which may not work with some serial devices. It does however work with the BV101 and BV103.
Serial Interface
As previously mentioned a BV102/3 can be plugged directly into the BV513-M
Connections and PC COM Port
| Pin | Description | Pin | Description |
| 2 | no connection | 1 | RX |
| 4 | Reset | 3 | TX |
| 6 | no connection | 5 | +V |
| 8 | CTS | 7 | no connection |
| 10 | RTS | 9 | GND |
- Reset: This is connected via a capacitor to the reset pin (pin 7 MCLR) of the PIC32. A pulse on this pin either positive or negative will reset the processor ·
- CTS: This is connected to port RB8. The default is not to use this pin and so could be used for other purposes.
- RTS: This is connected to port RB14. The default is not to use this pin and so could be used for other purposes.
- RX: Is the serial input to the processor which must be 0-3.3V logic. The pin used is RF4 and is UART2.
- TX: Is the serial output from the processor and is 0-3.3V logic. The pin used is RF5 and is UART2·
- +V: This pin is the input to the 3V3 regulator and so can be any voltage from 3.5V to 10V DC·
- no connection: Nothing is connected to these pins.
If a PC COM port is used then a MAX2323 (3.3v) or similar voltage translation device is required. It must NOT be directly connected to a PC COM port.
The above shows one possible arrangement for connection to a PC COM port using a MAX2323. The power for the MAX can be derived from the BV513-M as shown. The BV-COM terminal emulator (supplied free) can pulse the DTR line which can be used to reset the processor. This is shown as a dotted line because it is not essential for operation.