cdp68hc68s1 Intersil Corporation, cdp68hc68s1 Datasheet
cdp68hc68s1
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cdp68hc68s1 Summary of contents
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... Refer to the data sheet for the CDP68HCO5C4 for additional information regarding CDP68HCO5 microcomputers and their Serial Communications and Serial Peripheral Interfaces. The CDP68HC68S1 is supplied lead dual-in-line plastic package (E suffix), and lead small outline plastic pack- age (M suffix). ...
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... Block Diagram SCK TO XMIT FROM MCU REC SPI/SCI CONVERSION CS MODE CLOCK DIVIDER CLK A CDP68HC68S1 ARBITRATION COLLISION DETECTOR DETECTOR DETECTION WORD COUNTER CONTROL AND CLOCK GENERATOR B CONTROL IDLE 6-85 BUS+ BUS- IDLE AND TO OTHER SBI CHIPS ...
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... Out of Range Quiescent Device Current Clock Speed NOTE: Although 1MHz is generally used as an example throughout this datasheet, the maximum speed limit may be higher and depends upon user’s noise tolerance requirements. Specifications CDP68HC68S1 Thermal Information Thermal Resistance -0. +0.3V Plastic DIP Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 ...
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... NOTES: 1. SCI is the UART interface of a 68HCO5 MCU. The CDP68HC68S1 is compatable with most UART devices. 2. The three-state mode is only entered when using the Buffered SPI mode. In the three-state mode, only the XMIT, REC, and SCK pins are three-stated. The CONTROL and IDLE pins are al- ways active ...
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... No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see web site http://www.intersil.com CDP68HC68S1 DESCRIPTION This is the clock input that shall be divided by the SBIC (as described in Table 2) and used as an internal synchronizing clock ...
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... If the control pin is again puled low before the end of the stop bit, then the next start bit will begin at the end of the previous stop bit. FIGURE 3. SCK, CONTROL, AND IDLE SIGNALS DURING THE SPI MODE OF OPERATION CDP68HC68S1 bus actually “floats” logic level one, but must be driven to a logic level zero. Logic 0-bits always dominate over logic 1- bits on the bus. If two MCU’ ...
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... MCU coupled with an SBl chip) might contain address infor- mation telling where (to which node[s]) the message is tar- geted for or where the message came from. CDP68HC68S1 Other possibilities would be to identify the type of message sent (e.g. an instruction or just information) or the length of the message. The remaining bytes in each message can be merely data bytes that comprise the actual message ...
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... SPI mode, but goes high at the middle of the last data bit in other modes. FIGURE 6. EXAMPLE OF THE SCI CHIP OPERATING DURING BUS ARBITRATION CDP68HC68S1 other SBl chips sense the start bit and inhibit their microcom- puters from transmitting (again, after a 32 clock period arbi- tration window delay). Once the arbitration detector circuit has blocked an MCU’ ...
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... Using the CDP68HC68S1 Following are some hardware and software recommenda- tions for using CDP68HC68S1 Serial Bus Interface Chip. Requirements may vary depending upon the user’s system configuration. Hardware (General) The differential bus lines (BUS+ and BUS-) must be termi- nated with external resistors as shown in Figure 4 ...
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... CS pin to 1. SCI Mode, Software The procedure to follow for transmitting/receiving in the SCI mode is basically identical to that stated in the “Using the CDP68HC68S1-Software” section above, with the following exception: Start of Message Delay Transmitting a byte via the 68HC05 SCl port basically requires loading the byte into the MCU’ ...
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... End Of Message (EOM) (i.e. transmit a logic 1 for 10 contiguous bit times by creating a software delay). CDP68HC68S1 Framing Errors While in the SCl mode, the SBI chip is capable of detecting incoming framing errors. It will do this even though the incoming signal is also echoed to the user microcomputer, which should also detect the framing error via its’ ...
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... SPI data register after the SBl chip has already begun to load data into the SPl port. CDP68HC68S1 Sending Messages to Other Microcomputers on the Bus ln order to send a message to other microcomputers on the bus while in the SPI mode the user microcomputer should: 1 ...
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... SPl transfer speeds. The MCU should also, at this time, simultaneously load the next 2 bytes of data to be transmitted into the buffer. CDP68HC68S1 While it is transmitting and receiving the 2 bytes of data on the differential bus the SBl chip will not allow transfer of data to and from the user microcomputer ...
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... Including a 10-bit interval time out, via using a timer or software loop. 2. The user microprocessor can simply wait until it senses IDLE going low. CDP68HC68S1 Receiving Messages from Other Microcomputers on the Bus If the user microcomputer loses arbitration has no message to transmit and another microcomputer begins to send its message onto the bus, the SBI chip will begin to receive a message from the bus ...