Interfacing an External SPI Device with the CYUSBS234/236 DVK – KBA92331

Version 1
    Version: *A

     

    Question: How can you connect an external SPI device to the CYUSBS234/236 DVK?

     

    Answer:

    TheCYUSBS234 DVK has one Serial Communication Block (SCB) that can be configured as SPI, while the CYUSBS236 DVK has two SCBs (SCB0 and SCB1) that can be configured as SPI. By default, the SPI lines of the SCBs on both the DVKs are connected to the on-board SPI EEPROM(s) through jumpers (J17, J19, J20, and J21 for CYUSBS234; J17, J19, J20, J21, J24, J25, J26, and J27 for CYUSBS236). Table 1 provides details on the location of the SPI pins available on both of the DVKs and how to connect them for interfacing external SPI devices.

    Table 1. SPI Pin Mapping

                                                                                                                                                                                                                         
             CYUSBS234    CYUSBS236
             SCB    SCB0    SCB1
             On Board SPI
        EEPROM
        External SPI device    On Board SPI
        EEPROM
        External SPI
        device
        On Board SPI
        EEPROM
        External SPI
        device
        SSEL    Short Pin No:2
        and 3 of J19
        Remove the Jumper
        present on J19.
        Connect the SSEL
        line of the external
        SPI device to Pin
        No: 2 of J19
        Short Pin No:2
        and 3 of J19
        Remove the Jumper
        present on J19.
        Connect the SSEL
        line of the external
        SPI device to Pin
        No: 2 of J19
        Short Pin No:2
        and 3 of J26
        Remove the Jumper
        present on J26.
        Connect the SSEL
        line of the external
        SPI device to Pin
        No: 2 of J26
        SCLK    Short Pin No:2
        and 3 of J21
        Remove the Jumper
        present on J21.
        Connect the SCLK
        line of the external
        SPI device to Pin
        No: 2 of J21
        Short Pin No:2
        and 3 of J21
        Remove the Jumper
        present on J21.
        Connect the SCLK
        line of the external
        SPI device to Pin
        No: 2 of J21
        Short Pin No:2
        and 3 of J27
        Remove the Jumper
        present on J27.
        Connect the SCLK
        line of the external
        SPI device to Pin
        No: 2 of J27
        MISO    Short Pin No:2
        and 5 of J17
        Remove the Jumper
        present on J17.
        Connect the MISO
        line of the external
        SPI device to Pin
        No: 2 of J17
        Short Pin No:2
        and 5 of J17
        Remove the Jumper
        present on J17.
        Connect the MISO
        line of the external
        SPI device to Pin
        No: 2 of J17
        Short Pin No:2
        and 5 of J24
        Remove the Jumper
        present on J24.
        Connect the MISO
        line of the external
        SPI device to Pin
        No: 2 of J24
        MOSI    Short Pin No:2
        and 5 of J20
        Remove the Jumper
        present on J20.
        Connect the MOSI
        line of the external
        SPI device to Pin
        No: 2 of J20
        Short Pin No:2
        and 5 of J20
        Remove the Jumper
        present on J20.
        Connect the MOSI
        line of the external
        SPI device to Pin
        No: 2 of J20
        Short Pin No:2
        and 5 of J25
        Remove the Jumper
        present on J25.
        Connect the MOSI
        line of the external
        SPI device to Pin
        No: 2 of J25

    You can connect the SSEL, SCLK, MISO, and MOSI lines of the external device to the pin numbers given in Table 1. Refer to the CYUSBS234/236 DVK schematics for more details about the jumpers:

    CYUSBS234 USB TO SERIAL DVK BOARD

    CYUSBS236 USB TO SERIAL DVK BOARD

    Figure 1. SPI Connection of CY7C65211

    Figure 2. SPI connection of CY7C65215