RPC-UHF RADIOMETRIX [Radiometrix Ltd], RPC-UHF Datasheet
RPC-UHF
Related parts for RPC-UHF
RPC-UHF Summary of contents
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... A data packet received by the RPC’s transceiver is decoded, stored in a packet buffer and the Host microcontroller signalled that a valid packet is waiting to be uploaded. figure 1: RPC + Host µ µ µ µ -controller Radiometrix Ltd, RPC Radio Packet Controller 18 pin DIL IC 18 pin SO IC RPC-433-40 are RPC-UHF The RPC-module page 1 ...
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... Radiometrix Ltd, RPC page 2 ...
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... T OST RANSFERS If the host sets the TX Request line low a data transfer from the Host to the RPC will be initiated. Similarly the RPC will pull RX Request low when it requires to transfer data to the Host (this may polled or used to generate a Host interrupt ). The transfer protocol is fully asynchronous, i.e. the host may service another interrupt and then continue with the RPC transfer desirable that all transfers are completed quickly since the radio transceiver is disabled until the Host < ...
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... RANSMIT On receipt of a data packet from the host, the RPC will append to the packet - preamble, frame sync byte and an error check sum. The packet is then coded for mark:space balance and transmitted. A full 27 byte packet is transmitted in 13.8ms of TX air time (40kb/s + 5ms preamble) ...
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... HE OST NTERFACE 2.1 S IGNALS It is recommended that the RPC be assigned to a byte wide bi-directional I/O port on the host processor. The port must be such that the 4 data lines can be direction controlled without affecting the 4 handshake line. pin pin pin name number function TXR 6 TX Request ...
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... R & A EQUEST TX Request & TX Accept: RX Request & RX Accept: A packet transferred between host and RPC consists of between 1 and 28 bytes, the first byte of the packet is always the control byte. There are two classes of H OST 1. Data Packets: To the transmitter or from the receiver 2 ...
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... TX download timing diagram Notes: • The data bus must not be set to output until step 3. i.e. after the RPC has accepted the request. The bus may be left as an output until the entire packet has been transferred to the RPC, it should then be set back to input (default state). ...
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... Host reads the data and negates RX Accept (i.e. data has been accepted) Repeat steps 1-4 with MS nibble. figure 8: RX upload timing diagram Notes: • The RPC will turn off it's data bus drivers after the entire packet has been uploaded to the HOST. • See Appendix B and C. for example RPC driver subroutines. 2.2 H <> RPC P ...
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... Link control codes (connect/disconnect/ACK/NAK etc.) Data field 2.2.3 RPC M A EMORY CCESS The RPC’s EEPROM memory can be accessed by setting bit 7 in the control byte. Bit 6 (R/W flag) defines a memory read or write. The bits left define the address. figure 10: RPC memory access Radiometrix Ltd, RPC ATA ACKETS ...
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... Host issues just the control byte, with bit 6 (W/R) cleared, bit 7 (PT) set and the memory address. The RPC will respond with 2 bytes, the first is a control byte which is an echo of the control byte just issued by the host, this is useful if the host is using an interrupt handler. The 2nd byte is the memory contents ...
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... S OWER AVING The RPC has 4 levels of power saving selected by PS0 & PS1 in SWITCHES. Power saving is achieved by shutting down the Transceiver and the RPC for a period of time (O Idle state (i.e. nothing happening). During the O <50 µA typ. The RPC will still respond immediately to a Host TX Request but cannot receive radio signals. After the programmed O for valid preamble. ON time = PWR-> ...
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... Time-Out and reset if Host fails to reply to any request or handshake within 2.9s 3 EEPROM W E RITE NABLE This bit protects the EEPROM from accidental writes, it must be set to 1 prior to each byte write to the EEPROM (addresses 01h to 3Fh). This bit will be cleared by the RPC after each byte write. 3 ELF EST LAG Writing this switch will initiate a radio self test ...
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... RPCs could be attempting to transmit at the same time. The receiver is turned on and the channel is checked for preamble or data. If the channel is clear the RPC will go to transmit, if the channel is busy the RPC will delay by a random time (setable by TX-BACK-OFF in EEPROM) then try again for a clear channel ...
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... SER ONFIGURABLE ARAMETERS The EEPROM has address range 01h - 3Fh (63 Bytes) The first 15 BYTES (8 are defined) contain parameters used to control the RPC. figure 13: RPC’s EEPROM memory Radiometrix Ltd, RPC N page 14 ...
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... FF formula Wake-up message = W valid range Power Save 'Off' Time (RC controlled) LEEP IME The OFF time is controlled oscillator in the RPC which has a wide tolerance of +/- 30% address 03 default 05 formula Off-time = valid range ↔ ↔ ↔ ↔ ↔ ...
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... For normal operation of the RPC the TXR line must be held high for either 1ms reset pulse or 100ms after a power up. There are 9 test modes which are selected by a binary code applied to the RPC's data bus bit DIL switch or rotary HEX switch connected between the data bus and 0V will select the modes (the RPC has weak internal pull-up's) ...
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... Radiometrix Ltd, RPC D O (RXR RED LED = preamble detected) ETECTOR N D REAMBLE ETECTOR testing on spec. Analyser QUARE AVE OD YE DIAGRAM REAMBLE BURSTS , re-transmit any valid packets received P "RADIOMETRIX" and listen for echo ...
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... BiM-XXX-F this takes a maximum of 3ms), after the receiver has settled, the remaining portion is used by the receiving RPC to positively identify and phase lock onto the incoming the signal (this requires 15 cycles of preamble). The preamble may extended to wake-up a remote RPC in power saving mode ...
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... Each byte in the RPC's buffer is expanded into a 12 bit symbol prior to sending. The symbol coding has the following properties :- • Perfect 50:50 balance, i.e.. always 6 one's & 6 zero's • There are never more than 4 consecutive one's or zero's. This minimises the low frequency components in the code and allows fast settling times to be used for the receivers' data slicer. ...
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... All of the redundancy in the code is directed towards error checking. For an FM radio link using short packet lengths, e.g. RPC + BiM , packets are either 100 grossly corrupt unrecoverable. By the same reasoning, the Host is not informed when the RPC decoder aborts a packet decode since corrupt information is of little value ...
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... Example RPC driver subroutines for Arizona PIC16C73 figure 16: RPC to PIC - µ µ µ µ C interface Packet transfers to / from the RPC are best handled in the host by two subroutines :- OUT_BYTE & IN_BYTE Additionally LISTEN_BUS is called on completion of a packet transfer to the RPC to return the data bus to inputs (default state). ...
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... BSF RPC,RXA ANDLW B'11110000' ;JUST THE DATA ; IORWF INDF ; ; ; A BYTE HAS BEEN READ FROM THE RPC INTO ADDRESS POINTED AT BY FSR ; ;-------------------------------------------------------------------- ; Radiometrix Ltd, RPC :RXR LINE FROM THE RPC ;WE GOT A RX REQUEST YET? ; LOOP BACK AND WAIT READ THE LS NIBBLE FROM THE RPC ...
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... OUT_BYTE ;OUT_BYTE WRITE A BYTE FROM FILE POINTED TO BY FSR TO RPC ; W IS DESTROYED ; ; NOTE THIS ROUTINE WILL HANG THE HOST UNTIL THE RPC ; ACCEPTS THE TRANSFER OF TWO NIBBLES ; ; WARNING DETECTING A TXA FROM THE RPC (i.e. call LISTENBUS) ; OUT_BYTE SWAPF INDF,W ; ANDLW B'11110000' ;JUST THE NIBBLE IORLW B'00000010' ...
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... Example RPC driver subroutines for Motorola 68HC11 figure 17: RPC to HC11 µ µ µ µ -C interface Packet transfers to / from the RPC are best handled in the host by two subroutines :- OUT_BYTE & IN_BYTE Additionally LISTEN_BUS is called on completion of a packet transfer to the RPC to return the data bus to inputs (default state) ...
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... SAVE_X RMB 2 ********************************************************************** * SUBROUTINE: IN_BYTE ********************************************************************* *This subroutine is designed to be called by an interrupt handler to *read a byte from the RPC into a file pointed *Note: The interrupt handler should load the X register with the file address before calling this subroutine. IN_BYTE CLR SAVE_1 LDAB ...
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... SUBROUTINE: OUT_BYTE ********************************************************************** *This subroutine will output of one byte to the RPC. Register X *should contain the address of the memory location of the byte to be *send. *Note: that register X has to be pre-loaded before entering this * subroutine. OUT_BYTE LDAA 0,X ANDA #%00001111 LDAB PORTC ANDB #%11101111 ...
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... PPENDIX The RPC as a control IC Clock frequency All timings within the RPC (except sleep) are determined by the clock frequency. The standard frequency is 10.24MHz and all timings unless explicitly stated otherwise, assume this clock frequency. f clk The data rate = bit / s 256 Clock accuracy The RPC uses synchronous data transmission and requires an accurate reference clock ...
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Copyright notice This product data sheet is the original work and copyrighted property of Radiometrix Ltd. Reproduction in whole or in part must give clear acknowledgement to the copyright owner. Limitation of liability The information furnished by Radiometrix Ltd is ...