DEUTSCHMANN AUTOMATION UNIGATE IC, Инструкция по эксплуатации

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Synchronous interface Deutschmann Automation GmbH & Co. KG
22 Instruction manual UNIGATE
®
IC - Ethernet V. 2.9 5.7.13
5 Synchronous interface
5.1 Overview of the synchronous serial interface
The synchronous serial interface is an interface of the IC to clocked shift registers. About this it is
not only possible to input or output digital signals but also the addressing of DA- or AD-convert-
ers with clocked serial interface is possible as well as the connection of LEDs or reading in rotary
switches. Connection examples are stated in chapter 3.
The synchronous serial interface can also be used in products, that do not feature an own micro
controller (stand alone operation), in order to realize digital IO-modules for instance. Up to 256
signals for input and output each can be processed. The UNIGATE® IC’s firmware is responsible
for the different amount of input and output signals and takes on control for it.
The data exchange with the script is made with the commands "
Set ShiftRegisterInput-
Type / Set ShiftRegisterOutputType
" and "
Set ShiftRegisterInputBitLength
/ Set ShiftRegisterOutputBitLength
" and “
WriteShiftRegister
“ as well as
“
ReadShiftRegister
“.
In order to make the use of the synchronous serial interface as efficient as possible, it is possible
to set a „
shift register
“ and a „
bit length
“ via the script, whereas both can be changed
dynamically within the script by script commands.
As a result the firmware is in the position to control the entire data transfer with the hardware and
the data exchange can be carried out as quickly as possible.
At present the shift register types "
RiseClk_RiseLoad
" and "
RiseClk_LowLoad
" are imple-
mented, that are required when using for instance the 74595 and 74165 (see also chapter 5.2).
Other types can be complemented very fast and simple - by Deutschmann Automation GmbH.
The shift register type defines the edges or the levels on how data is output to the hardware or
how data is read in.
In this case the data exchange is restricted to the script commands "
WriteShiftRegister
"
and "
ReadShiftRegister
". The clock speed is min. 150kHz, so that for instance a shift regis-
ter with 32 bit is read in or written in a time period of max. 215µs.
5.2 Script-example
var InBuffer: Buffer[2];
Var OutBuffer: Buffer[2];
MoveConst (OutBuffer[0], #0x58#0x21 ),
Set ( ShiftRegisterInputType , RiseClock_FallLoad ) ;
Set ( ShiftRegisterOutputType , RiseClock_RiseLoad ) ;
Set ( ShiftRegisterInputBitLength , 16 ) ;
Set ( ShiftRegisterOutputBitLength , 16 ) ;
WriteShiftRegister ( OutBuffer[0] ) :
ReadShiftRegister ( InBuffer[0] ) ;
// Input data is now in the InBuffer
// 0x58 is applied to the outputs of the analog converter
// 0x21 at the shift register’s outputs