Hello everyone,
I’d like you to inform you about a nice system I encountered.
My son is following a subject "Computer Systems" and to my surprise it involves a practicum with a so called "PP2 practicum board", an assembler written in java, an emulator also written in java and the complete documentation.
Attachment:
PP2ManualB v2 identical_page2_image1.png [ 465.37 KiB | Viewed 1405 times ]
The development board consists of a Spartan 3E on a (which looks like) GODIL_XC3S500E board or similar.
http://shop.trenz-electronic.de/catalog ... cts_id=630The FPGA is pre programmed as an 18-bit CPU following the Von Neumann architecture.
http://en.wikipedia.org/wiki/Von_Neumann_architecture It has 20kB of 18-bit RAM. The CPU called PP2 runs at approximately 35 mhz. It has 8 general purpose registers R0-R7. The assembler and the CPU work with relocatable code and relocatable data! Data can be accessed by indexing with a so called Global Base register (equal to R6). It has a resizable Stack Pointer (equal to R7).
Further there are 8 tactile buttons, 8 LED’s, 6 7-segment displays, a potentiometer, and 3 on/off switches with LED’s, a timer and a serial interface up to 115200 baud. Those I/O devices are allocated to memory locations -1 to -16 (two complement)
Well, what does it have to do with the 6502? Easy enough:
Code:
LOAD
ADD
SUB
CMP
MULS
MULL
DIV
MOD
DVMD
AND
OR
XOR
STOR
JMP
JSR
BRA
BRS
BEQ
BNE
BCS
BCC
BLS
BHI
BVC
BVS
BPL
BMI
BLT
BGE
BLE
BGT
RTS
PULL
PUSH
It’s very easy to adapt and write in that assembly language. One feels instantly at home.
As far as I can determine, branch instructions can reach the whole address space of 18 bit in two complement. So from -131072 upto 131071. That’s fantastic. It has no shift instructions, but those can be achieved by MUL and DIV. Multiplications can be 18 bit with overflow (MULS) or 36 bit with overflow (MULL). Wow.
Does anyone of you know of this system?
Making such a similar board based on the W65C02 or W65C816 would be great for newbie’s (including myself). Providing a complete manual and a number of exercises with solutions in PDF format.