Table of Contents
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Table of Contents
DiagRC, A Diagnostic Module for RC2014
Introduction
DiagRC is a low cost programmable multi-function logic analyzer and diagnostic aids for bringing up a RC2014 system. The board is similar to protoRC rev3 (picture below), but without the prototype area.
Features
Altera EPM7064SLC44
RC2014 bus interface
Local oscillator
Serial port for CP2102 USB-serial adapter
Programming header for Altera CPLD
Two modes of operations
Logic analyzer
Hardware diagnostic
2-layer PCB, 100mmX50mm
Theory of Operation
DiagRC is based on CPLD and can be reprogrammed for different modes of operations. The CPLD is socketed so for users without Altera programmer, different mode of operations can be achieved by inserting the appropriately programmed CPLD in the socket. The modes of operation are:
Logic Analyzer
In the logic analyzer mode of operation, DiagRC monitors RC2014 bus activities and display them in real time over a high speed serial port. An reasonably achievable serial port speed is 460K. To prevent overrun of serial data, the CPU clock of RC2014 needs to be slowed down significantly to about 10KHz.
Hardware Diagnostic
In the hardware diagnostic mode of operation, DiagRC becomes a small ROM with a serial port transmitter. The program in the small ROM run memory diagnostic and initialize I/O and send status information out of the serial port transmitter. RC2014 hardware setup can be as simple as just the CPU card and DiagRC, or as complex as CPU, RAM, SIO2, digital I/O, and CF. The clock board and ROM board are not used in hardware diagnostic operation.
Design Info for Hardware Diagnostic Board
Gerber photoplots
Build of Materials
CPLD design files
Logic Analyzer design file
Hardware Diagnostic design file
Schematic of hardware diagnostic CPLD
Modification to ProtoRC, rev 3 to enable hardware diagnostic function
The following jumpers to required to make protoRC rev3 into a hardware diagnostic module
Test points connections:
T1 to RC2014 A15
T2 to RC2014 A14
T3 to RC2014 A13
T4 to RC2014 A12
T5 to RC2014 A11
T6 to RC2014 A10
T7 to RC2014 A9
T8 to RC2014 D0
T9 to RC2014 D1
T10 to RC2014 D2
T11 to RC2014 D3
T12 to RC2014 D4
T13 to RC2014 D5
T14 to RC2014 D6
T15 to RC2014 D7
6-pin Serial port
Ground (pin 5) to T33
Transmit (pin 2) to R11 (LED current limiting resistor)
Clock to external clock
T37 to RC2014 CLK