Boris3 Introduction

THE MICRO-PROCESSORS
There are three micro-processors on the Borris3 motherboard - the 68340 (U1), the TMS320C25 (U200) and the ST90R50 (U300). The 68340 is basically in charge and assigns various tasks for the other two processors to perform.
The 68340 is used to control its own memory management, user interface as well as the following devices :-

The TMS320C25 is a dedicated digital signal processor. It is used to perform all the number crunching operations. It performs all the complex cross fade calculations and forms an integral component of the Digital Output Module (DOM). 

The ST90R50 is used for reading the following devices :-

PROGRAMMABLE DEVICES.
As well as the three micro-processors, there are also various programmable devices on Borris3. These are given a unique name for ease of reference. 

68340 Processor

THE 68340 PROCESSOR AND MEMORY
The 68340 and associated memory forms the central part of the Borris3 motherboard design.
The 68340 has a number of features which include two serial ports, a number of port lines, DMA channels and four chip select lines.

The chip select lines are used as follows:-

PROGRAMMING THE FLASH MEMORY.
During programming of the flash memory, the OE signal must be held high.
This is achieved by setting port pins 4 & 5 of the 68340 to 1.
However at power up these pins are selected to be inputs. Therefore, pull-down resistors R7 & R11 are employed to hold these pins low at power-up.
Therefore, resistors R7 and R11 are critical to the operation of the whole circuit! 

BATTERY BACK-UP.
All the SRAM are battery backed by BAT1, which has a life expectancy in the order of 5 years.
Care should be taken when storing and handling the circuit board to ensure the battery is not shorted out.

ON-BOARD DIAGNOSTIC DISPLAY.
A 4 character display (DIS1) is included to simplify the task of board testing.
The minimum requirement for this to operate is:-

68340 PORT PINS
The 68340 port A is used as follows :-

68340 INTERRUPT USAGE.

REAL TIME CLOCK (RTC)
A real time clock chip (DS1302 - U22 ) is used to provide time keeping even when the system is powered down.
Three port pins of the 68340 CPU (PA1 - PA3) are used to set the time and date.
First a RTC-RST signal is applied, then a command is clocked using RTC-SCLK to clock data into the DS1302 whilst the RTC-IO pin is used to carry the data.
There are 24 bytes of additional RAM allocated for use within the RTC.

RESET CIRCUITRY
A MAX6315 device (U34) is used to monitor and control the 68K reset signal. It issues a reset to the 68K CPU during power-up, power-down, and brownout conditions.
This device offers greater system stability because it is relatively immune to short-duration negative-going transients (glitches).

The MAX6315 also has provision for a manual reset switch to be added thus allowing the operator to initiate a reset. External debounce circuitry is not required. Connecting a 100nF capacitor (C24) from MR to ground will also provide additional noise immunity.

USER LINKS
A set of eight user defined links (L3) are provided for system settings under software control.

SERIAL PORTS
The 68K is equipped with two serial ports - Port A & Port B.
 
Port A is used for a general purpose serial interface using the 25 way female D-Type connector (DEE1).
This RS-232 port can be connected to the Graphics Tablet, the Riggers Remote or the Room Controller.
 
Port B is used for the MIDI Port (DIN60 & DIN61).
A 500kHz MIDI clock signal is also supplied to the SCLK pin 88 of the 68K by U7 (EXO16).
Note that the RTSB signal is configured as an output port and is used to communicate with the BIO signal of the TMS320C25 (DOM).

Digital Output Module

DMX OUTPUT PINOUTS
 

ST90R50 Processor

ST9 KE LOOM - IDC34
To keep compatibility with the PEARL and allow keyboard expansion for the Diamond and Sapphire the KE connector (IDC34) has been retained.
Pins 1 to 8 are input lines, buffered by a 74HC245 (U23) with a pull-up resistor network (RN1) fitted.
Pins 9 to 20 are used to provide twelve keyboard write strobes (KW01-12). These are all output port pins from the ST9

ST9 DB LOOM - IDC31
An enhanced DB loom is provided which allows access to the ST9's data, address and some control lines.
All signals to this loom are buffered by 74HC245 devices (U312, U24 & U18).

SPI LOOM - IDC30
This is a standard SPI port, taken out on a 10 way IDC header.
Pin 1 = RxD,   Pin 2 = CLK    and  Pin 3 = TxD.
Pins 4 - 7 are select lines from port pins of the ST9.

ST9 to 68K INTERFACE
The ST9 communicates with the 68K by a (4K * 8bit) Dual Port Ram (U301).
The 68K downloads some program code to the (32K * 8bit) ST9 SRAM (U27). The ST9 then runs this code to perform the various ST9 tasks like key scanning, DMX input processing and reading the QWERTY keyboard.
Thus by using the SRAM to run ST9 code, the need for an awkward and expensive ST9 OTP (one time programmable) device can be alleviated.

The KOLYA gal (GAL8) forms an integral part of the ST9 system by providing various select signals (SEL17, SEL19 & SEL25) to the ST9 DB LOOM and also proving decode signals to the Dual Port Ram and SRAM.

QWERTY KEYBOARD
A standard QWERTY PC keyboard can be connected to Borris3 via the 6pin mini DIN socket (DIN1). Power to the keyboard is provided by a resettable fuse (F1). Keyboard data (QWERTY-DATA) is read by the ST9 port pin 8.1. The keyboard clock (QWERTY-CLK) signal is sent to the ST9 interrupt pin INT3. A pull-up resistor (R16) is also employed on this pin.

DMX INPUT
A 5 pin male XLR (XLR4) is used to supply the ST9 with DMX data.
Input protection to 240VAC is offered in the form of two 100R PTC thermistors (PT13 & PT14) and two transient voltage suppressors (D17 & D18). DMX input termination is also provided in the form of a 100R PTC thermistor (PT15).

Sound To Light

The sound to light filter circuit produces three trigger signals :-
Low, Mid and High as well as a Clip one to indicate signal overload.

The trigger signals are then sent to a 74HC245 buffer (U507), which is then read by the 68340. This buffer is enabled by KATYA (GAL1) using the DC2PORT signal.

Video Card

The VIC gal (GAL6) creates the correct strobe lines from the video select signals VIDSEL1 and LSEL1. Note that the video card requires an active high reset signal for correct operation. This is generated by a 74LS04 (U10-E) which inverts the 68340's reset signal. 

Floppy Disk Drive

A standard PC floppy disk drive can be connected to Borris3.
The 34-way data cable from the disk drive connects to IDC500 whilst the 4-way power loom connects to the header labelled FLOPPY on Borris3.
A Floppy Disk Controller chip, FDC37C78 (U505) is used to interface the Disk Drive with the 68K processor. The KATYA gal (GAL1) is used to provide all the control signals to the controller chip.
Note that the controller chip requires an active high reset signal for correct operation. This is generated by a 74LS04 (U10-E) which inverts the 68340's reset signal. 

Universal Serial Bus (USB)

A Universal Serial Bus port on Borris3 now allows for communication with a standard PC motherboard.

Changes between Boris2 and Boris3

SMD DEVICES ON BORIS3

NOTE: 
To avoid confusion, component references in BOLD REFER TO BORIS2 whilst component references in BOLD ITALICS REFER TO Boris3.

68340 PROCESSOR MEMORY
The SIL extended memory modules (IC106 & IC107), utilising the MCS3 chip select line, have been replaced by a pair of Flash EPROM chips (ROM2L & ROM2U).
This means that the battery back up chip DS1210 (IC114) is no longer required.

RESET CIRCUIT
A MAX6315 device (U34) is now used to monitor and control the 68340 reset signal. It issues a master reset to the 68K CPU during power-up, power-down, and brownout conditions.
This master signal is then buffered by two LS04 inverters (U10) before being fed to the rest of the circuit.
Note that U10-E is used to generate an active high reset signal for the VGA and Floppy Disk Drive devices.
The MAX6315 device offers greater system stability as it is relatively immune to voltage transients (glitches) on the power supply.

The MAX6315 also has provision for a manual reset switch (with internal debounce circuitry) - thus isolating the master reset signal from the external one.
Connecting a 100nF capacitor (C24) from this external signal to ground also provides additional immunity in noisy environments.

THE ST90 PROCESSOR
The ST90R40 processor (IC300) on Borris2 will soon become obsolete. We have therefore replaced it with the ST90R50 (U300).
As the ST90R50 is equipped with a dedicated address and data bus, the 74LS373 (IC301) latch used on Borris2 is no longer required.

Two pull-up resistors (R18 & R19) have also been added to the SPI TxD and CLK signals - again to improve noise immunity.

Two 74HC245 buffers ( U24 and U18) have been added to the ST9 DB Loom (IDC31). These allow greater integrity of the ST90's address and control signals whilst driving a capacitive load (i.e. a ribbon cable).

QWERTY KEYBOARD
The keyboard connector on Borris3 (DIN1) has been changed to a Mini-Din one so that it will now accept a standard PC keyboard.
A pull-up resistor (R16) has also been added to the clock signal to improve noise immunity.

DMX OUTPUTS
All DMX outputs on Borris3 are now fitted with protection to 240VAC and also meets EMC immunity requirements.
This is achieved by using a pair of 33R 240V PTC thermistors and 5W 6V2 zener diodes on each of the DMX outputs.
This protection is fitted between the output XLR's and the DMX line drivers (75174).
A set of 1W DC-DC converters (NME0505S) are also used to provide an isolated output to the DMX line drivers (75174) and DMX opto-isolators (6N137). This provides a 1kVDC isolation.
One DC-DC converter is used to provide isolation for two DMX outputs.

DMX INPUT
Borris3 also offers Input protection to 240VAC in the form of two 100R PTC thermistors (PT13 & PT14) and two transient voltage suppressors (D17 & D18).
DMX input termination is also provided in the form of a 100R PTC thermistor (PT15).

FLOPPY DISK CONTROLLER
The 37C65 Floppy Disk Controller chip (IC505) used on Borris2 has become obsolete.
This has been replaced by a new 37C78 SMD controller (U505).
The 68340 uses different control signals to control this chip - hence it requires an updated Katya gal. 

POWER SUPPLY
Borris3 is now fitted with an optional 20-Way ATX type connector (PSU-ATX).

ONBOARD FUSES
All fuses are now off the resettable type - once a faulty condition has occurred, the fuse will trip.
To reset the fuse, simply power down the desk, rectify the fault and  switch the desk back on.
Extra fuses have also been added for the Littlite connector +5V (F5) and the Qwerty keyboard +5V (F1).

UNIVERSAL SERIAL BUS
A USB port on Borris3 now allows for communication with a standard PC motherboard.

BORRIS1 TO BORRIS3 UPGRADE
The Borris3 motherboard has been carefully designed so that it can now be fitted into "old style" Pearl desks that were fitted with a Borris1 motherboard.
To do this, a Borris3 pcb has to be specially assembled so that none of the Input/Output connectors are fitted.
Instead, a set of molex headers are fitted in their place which will connect to connectors on the Pearl rear panel (i.e. DMX XLR's, MIDI & Sound to Light Connectors etc.)

The VGA Video card is the mounted to Borris3 using four of its fixing holes.

The Power Supply

The Borris3 motherboard is designed to accept a standard PC Power Supply - either an AT or ATX type PSU can be fitted.
Note that an AT PSU is normally fitted as standard - this uses connectors P8 and P9 on the motherboard.
If an ATX PSU is to be used, first check that the connector labelled PSU-ATX is fitted to the Borris3 motherboard.
 
There is also provision to use a smaller NLP40-7608 PSU - this uses the connector labelled AZ-PSU.
 
Three LED's monitor the power supply status on Borris3.

Pictures

DMX Outputs

Wipe All and Program Links