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8051 and SCC2692 uart

Started by Folkert van Heusden December 15, 2006
Hi,

My boss gave me an embedded device with a 8051 processor coupled to a 
SCC2692 (by Philips) uart and the Keil c compiler. Now I was ordered to 
develop some kind of pc-interface.
The problem now is: I have absolutely now idea how to access this SCC2692 
uart.
I have documentation the chip, but how am I supposed to fiddle with it? Is 
it memory mapped? Does the 8051 have special io-instructions?
All help is appreciated!


Folkert van Heusden
www.vanheusden.com [private website] 


Folkert van Heusden wrote:
> Hi, > > My boss gave me an embedded device with a 8051 processor coupled to a > SCC2692 (by Philips) uart and the Keil c compiler. Now I was ordered to > develop some kind of pc-interface. > The problem now is: I have absolutely now idea how to access this SCC2692 > uart. > I have documentation the chip, but how am I supposed to fiddle with it? Is > it memory mapped? Does the 8051 have special io-instructions? > All help is appreciated! > > > Folkert van Heusden > www.vanheusden.com [private website] > >
Do you have the right data sheet ? http://www.nxp.com/acrobat_download/datasheets/SCC2692_3.pdf Its an 8-bit parallel buss. If you have an embedded devices with an 8051 and SCC2692, then its already wired, so do you have a schematic of this board ?? Here are few app notes: http://www.nxp.com/pip/SCC2692AC1N28.html I have not used this part before, but if you have done any 8051 development before this should be easy. Good luck donald
Folkert van Heusden wrote:

>Hi, > >My boss gave me an embedded device with a 8051 processor coupled to a >SCC2692 (by Philips) uart and the Keil c compiler. Now I was ordered to >develop some kind of pc-interface. >The problem now is: I have absolutely now idea how to access this SCC2692 >uart. >I have documentation the chip, but how am I supposed to fiddle with it? Is >it memory mapped?
Probably, but not neccessarily. In any event, this is all determined by the board design. You're going to have to analyize the board's schematic to determine the answers to your questions.
> Does the 8051 have special io-instructions?
The 8051 uses the Harvard architecture so it has seperate code and data spaces and its special function registes that control the I/O ports are in a third space, but it does not have a seperate I/O space, per se.
>All help is appreciated!
I suggest that you point your browser to http://www.8052.com/ and avail yourself of the wealth of knowledge and resources there. -- ======================================================================== Michael Kesti | "And like, one and one don't make | two, one and one make one." mrkesti at hotmail dot com | - The Who, Bargain
In article <458291a2$0$13428$e4fe514c@dreader29.news.xs4all.nl>, Folkert 
van Heusden <folkert@vanheusden.com> writes
>Hi, > >My boss gave me an embedded device with a 8051 processor coupled to a >SCC2692 (by Philips) uart and the Keil c compiler. Now I was ordered to >develop some kind of pc-interface. >The problem now is: I have absolutely now idea how to access this SCC2692 >uart. >I have documentation the chip, but how am I supposed to fiddle with it? Is >it memory mapped? Does the 8051 have special io-instructions? >All help is appreciated! >Folkert van Heusden >www.vanheusden.com [private website]
Hi, 1 ALL 8051's have a serial port built in. Use that to start with. 2 Which (of the 0ver 600) 8051 variant is it? Some have an external address and data bus some do not. 3 Are you sure your PC has an RS232 serial port. 4 the Keil web site has information on using the on board serial port. 5 have a look at the C51 primer. http://www.phaedsys.demon.co.uk/chris/papers/QuEST4_1.pdf -- \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ \/\/\/\/\ Chris Hills Staffs England /\/\/\/\/ /\/\/ chris@phaedsys.org www.phaedsys.org \/\/\ \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
On Fri, 15 Dec 2006 13:14:26 +0100, "Folkert van Heusden"
<folkert@vanheusden.com> wrote:

>My boss gave me an embedded device with a 8051 processor coupled to a >SCC2692 (by Philips) uart and the Keil c compiler. Now I was ordered to >develop some kind of pc-interface. >The problem now is: I have absolutely now idea how to access this SCC2692 >uart. >I have documentation the chip, but how am I supposed to fiddle with it? Is >it memory mapped? Does the 8051 have special io-instructions? >All help is appreciated!
Get the schematic for the embedded device. From that, you will be able to deduce how to access the UART. -- Dan Henry
I second that motion .  "Get the schematic" !

It is pointless doing anything unless you have the schematic diagram and 
possibly some comments from the original firmware/hardware designers.

The schematic should tell you weather the SCC2692 is memory mapped in to the 
data space (RAM area)  or  it is controller by the general purpose I/O pins.

A memory mapped SC2692  will be controlled by read/writes to memory 
location.

Am I/O controller SCC2692 will be controller by  port pin I/O commands.... 
in quite a few cases the I/O operations will emulate memory control so the 
SCC2692  thinks it is connected to a memory bus
(8 I/O lines are the data bus and a few others are read, write, chip select, 
A0 and A1).

Regards
Joe


"Dan Henry" <usenet@danlhenry.com> wrote in message 
news:mp06o29mkf5q39hhgfrjl87g786jtim6ar@4ax.com...
> On Fri, 15 Dec 2006 13:14:26 +0100, "Folkert van Heusden" > <folkert@vanheusden.com> wrote: > >>My boss gave me an embedded device with a 8051 processor coupled to a >>SCC2692 (by Philips) uart and the Keil c compiler. Now I was ordered to >>develop some kind of pc-interface. >>The problem now is: I have absolutely now idea how to access this SCC2692 >>uart. >>I have documentation the chip, but how am I supposed to fiddle with it? Is >>it memory mapped? Does the 8051 have special io-instructions? >>All help is appreciated! > > Get the schematic for the embedded device. From that, you will be > able to deduce how to access the UART. > > -- > Dan Henry

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