Abstract:
A distributed-type input/output control IC is proposed to provide an integrated type improvement to the conventional remote control system. The distributed-type input/output control IC comprises a plurality of local digital IO and a plurality of remote IO master to control a plurality sets of local and remote systems and to simplify wiring.

Description:
FIELD OF THE INVENTION 
     The present invention relates to an integral-type IC for distributed-type input/output control to provide input/output control for remote end, thus simplifies wiring and maintenance. 
     BACKGROUND OF THE INVENTION 
     The application-specific integrated circuit (ASIC) for automatic control system becomes popular due to the rapid development of semiconductor technology. For examples, micro-controller, multiplexer and embedded microprocessor have found wide application. 
     However, the wiring of the automatic control system is complicated, especially for multi-module. Taking a six-slave module as an example, each set of module has 64 input/output lines. The number of total input and output lines is 128. Therefore, the number of wiring for the six-slave module is 768. The wiring and maintenance of the system is troublesome. 
     The object of the present invention is to provide an IC that simplifies the I/O control of the wiring. 
     In one aspect of the invention, the integral-type IC for distributed-type input/output control can control multiple remote and local I/O connection to simplify wiring. 
     To achieve above and other objects, the IC of the present invention comprises a plurality of local digital IO for controlling the local I/O and remote IO master which perform command from ISA BUS to transmit signal in CRC format to remote end and vice versa. 
     The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawings, in which: 
    
    
     BRIEF DESCRIPTION OF DRAWING 
     FIG. 1 is the block diagram of the invention 
     FIG. 2 is the block diagram of the remote IO master. 
     FIG. 3 is the block diagram of the local digital IO. 
     FIG. 4 is the block diagram of the auxiliary circuit in the distributed-type input/output control IC. 
     FIG. 5 is the block diagram of the slave IO mode. 
     FIG. 6 is the circuit diagram of the slave module. 
     FIG. 7 is the circuit diagram of the first group of slave module circuit. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is intended to provide an integral-type IC for distributed-type input/output control which can control multiple remote and local I/O in an integral way, thus simplifies wiring and maintenance. 
     FIG. 1 is the block diagram of the invention. The integral-type IC  10  for distributed-type input/output control is an ASIC and control multiple local systems remotely. It should be stressed that the system can be classified to master mode and slave mode wherein the system shown in FIG. 1 is the slave mode. 
     The distributed-type input/output control IC  10  comprises a plurality of local digital IO  20  to control local input/output such as a plurality of switches and lamps, and a remote IO master  30  to execute command from a bus and transmit data in CRC format to remote end through a single transmission line and vice versa. 
     FIG. 2 is the block diagram of the remote IO master  30 , which comprises a control unit  300  to control each functional block in the remote IO master  30 , an input data CRC checker  301  for checking the CRC error of the input data, a shift register  302  connected to the input data CRC checker  301  to register the remote data, an output data CRC generator  307  connected to the shift register  302  to generate error detection information for the data output by the remote IO master  30 . 
     The remote IO master  30  also comprises an output latch  303  to latch the plurality of data sent from distributed-type input/output control IC  10  to remote end, a multiplexer  304  connected to the output of the output latch  303  to multiplex three data as one set data and transmit the data to the shift register  302 , a de-multiplexer  305  connected to the shift register  302  to de multiplex the data sent to the distributed-type input/output control IC  10  into three set of data, and an input latch  306  to latch the data to be sent to the distributed-type input/output control IC  10 . 
     FIG. 3 is the block diagram of the local digital IO  20  in the distributed-type input/output control IC  10 . The local digital IO  20  comprises a digital input latch  202  to latch the data from the connected digital circuit to the distributed-type input/output control IC  10 , a digital out latch  204  connected to an output enable  206  to latch the data from the distributed-type input/output control IC  10  to the digital circuit to be connected and control the output enable. In the preferred embodiment of the invention, there are seven sets of local digital IO  20 , and each set is connected to four input/output circuits. 
     FIG. 4 is the block diagram of the auxiliary circuit in the distributed-type input/output control IC. The IC  10  also comprises a bus interface  102  for the interface of data transfer with CPU, an interrupt controller  104  for controlling the interrupt vector of the CPU, a waiting state generator  106  for setting the waiting time of CPU when accessing the IC  10 , and an address decoder  108  for dealing the address decoding process between the CPU and the IC  10 . 
     The present invention can be adopted to be remote IO master or to be salve IO mode. FIG. 5 is the block diagram of the slave IO mode, wherein numeral  10  denotes the master mode IC and is the distributed-type input/output control IC in FIG. 1, and  10 ′ denotes the slave mode distributed-type input/output control IC. Both the IC  10  and  10 ′ are of the same IC but with different internal circuits for different operation mode. The master mode distributed-type input/output control IC  10  is connected to a plurality of control circuits (i.e. digital input/output circuit) and the adopts serial IO interface as protocol therebetween. 
     As shown in FIG. 5, the set of slave IO module and interfacing circuit  90  comprises the first group of slave module circuit  91 , the second group of slave module circuit  92 , and the third group of slave module circuit  93 . Each group of slave module circuit  91 ,  92  or  93  comprises a slave mode distributed-type input/output control IC  10 ′. The salve IO module and interfacing circuit  90  and the master mode distributed-type input/output control IC  10  are connected through serial IO interface and there are six signal lines in this embodiment. 
     It should be noted the master mode IC and the salve mode IC shown in FIG. 5 should be matched to each other to send data to remote end. 
     In above-mentioned embodiment, the slave module circuit  91 ,  92  or  93  is connected to external I/O unit through 64×2=128 I/O ports while each slave module circuit is connected to the master mode distributed-type input/output control IC  10  through only 4 signal lines. In other word, the wiring can be reduced from 128 to 4 by the present invention. 
     FIG. 6 is the circuit diagram of the slave mode distributed-type input/output control IC  10 ′. As shown in FIG. 6, the IC  10 ′ comprises a control unit  910  to control other members of the distributed-type input/output control IC in slave mode, an input buffer  911  to buff the data to be sent to the slave mode distributed-type input/output control IC  10 ′, a shift register  913  connected to the input buffer  911  for registering data, and an input data CRC checker  912  connected to the shift register  913  to check the CRC error for the input data. 
     Moreover, the slave mode distributed-type input/output control IC  10 ′ further comprises an output latch  914  to latch the output data of the slave mode distributed-type input/output control IC  10 ′, and an output data CRC generator  915  to generate error detection information for the data output by the slave mode distributed-type input/output control IC  10 . 
     FIG. 7 is the circuit diagram of the first group of slave module circuit  91  while other lave module circuits  92  and  93  have the same circuits. The first group of slave module circuit  91  comprises a slave mode distributed-type input/output control IC  10 ′ for digital IO control, a  64  input interface  919  to receive external input and a  64  output interface  92  to transmit a output signal t the connected switch or lamp. 
     To sum up, the inventive integral-type IC for distributed-type input/output control can integrate the IO connection of a plurality of remote ends into an ASIC, thus simplifies wiring and maintenance. 
     Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.