Call for SPARCengine 1e BSP

[Joel Sherrill <joel@OARcorp.com>]

Ivan Galkin wrote:
> 
> Jiri, many thanks for these important clarifications.
> I only wish we knew that this sparc v7 board won't work a month ago.
> We do need VME to control our VME hardware and sync to its timing.
> I don't think we are going to spend $18K on a TSC695 starter kit. Does 
> not sound right.
> MiThOS will work on sun4e, but their development is defunct, and they 
> never wrote a VME driver.
> We are leaning towards scratching the idea and moving to an intel vme 
> board. This will mean different bsp, vme, endian, CPU speed. But its 
> better than sun4e, apparently.
> Something like vp101 by ArcTechnico. This brings another question - do 
> we order a linux VME driver from ActTechnico, hoping that we can make it 
> work in Rtems? Another option in a VxWorks vme driver.

Depending on what your CPU desire is, the Motorola PowerPC VMEBus boards
have an active RTEMS user community.

If you are trying to do this on the cheap, then a used MVME162 or
MVME167 might make a nice option.

The x86 VMEbus boards should work as well but you would probably have to
adapt the VMEbus driver.

--joel

> Thanks again,
> Ivan
> 
> 
> 
> Jiri Gaisler wrote:
> 
>>
>> Since you asked, here my view on the topic ...
>>
>> The ERC32 is not very similar to the Fujitsu MB86901A
>> processor used in the Sparcengine 1e. The integer
>> pipeline implements the same SPARC V7 instruction set,
>> but the memory hierarchy is completely different.
>> MB86901A has a cache, an MMU, and DRAM main memory.
>> ERC32 has no cache, no MMU and executes directly
>> from 0-waitstate external static RAM. The peripherals
>> (uart, timers, irq ctrl, I/O) are completely different.
>> I also believe that the MB86901A has 7  register
>> windows while ERC32 (based on Cypress 601) has 8.
>>
>> It should be possible to develop an SS 1E bsp, but
>> all low level code (drivers and init) will becdifferent
>> from ERC32. So the only RTEMS part you really can
>> reuse is the general SPARC support. The complete
>> bsp and associated drivers must be written from
>> scratch. This means that you need detailed
>> data sheets with register definitions, address
>> allocation and interrupt routing. Unless you
>> have that, it will be very difficult (impossible?).
>>
>> If you really want some cheap SPARC hardware,
>> why not get a low-cost FPGA board (~ $500) and
>> put a LEON3 on it. There is a stable RTEMS bsp
>> for it (yes, I will soon merge it in to the main tree)
>> and the VHDL code and development tools are free.
>> OK, there is no VME but do you really need that?
>>
>> An other aspect is that we have today announced
>> the availability of LEON3FT parts on the Actel
>> RTAX2000 radiation-hardened FPGA devices. There
>> will be various pre-programmed LEON3FT devices
>> with 1553, CAN-2.0 and Spacewire available, as well
>> as netlists if you want to make you own FPGA config.
>> Performance is 20 - 30 MHz, on par or better than ERC32,
>> but with only ~ 0.5W power consumption. For software
>> development, you can use cheap Xilinx/ALtera boards
>> or a commercial grade AX2000 device (~ $250).
>> Debugging is also significantly easier than ERC32,
>> you have a real on-chip debug support unit, with
>> single-stepping, tracing and memory/register access.
>>
>> Jiri.
> 
> 


-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel at OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
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