Entity: neorv32_spi
- File: neorv32_spi.vhd
Diagram
Description
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<< NEORV32 - Serial Peripheral Interface Controller (SPI) >>
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Frame format: 8/16/24/32-bit receive/transmit data, always MSB first, 2 clock modes,
8 pre-scaled clocks (derived from system clock), 8 dedicated chip-select lines (low-active).
Interrupt: SPI_transfer_done
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BSD 3-Clause License
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Copyright (c) 2021, Stephan Nolting. All rights reserved.
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Redistribution and use in source and binary forms, with or without modification, are
permitted provided that the following conditions are met:
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1. Redistributions of source code must retain the above copyright notice, this list of
conditions and the following disclaimer.
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2. Redistributions in binary form must reproduce the above copyright notice, this list of
conditions and the following disclaimer in the documentation and/or other materials
provided with the distribution.
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3. Neither the name of the copyright holder nor the names of its contributors may be used to
endorse or promote products derived from this software without specific prior written
permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
OF THE POSSIBILITY OF SUCH DAMAGE.
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The NEORV32 Processor - https://github.com/stnolting/neorv32 (c) Stephan Nolting
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Ports
| Port name | Direction | Type | Description |
|---|---|---|---|
| clk_i | in | std_ulogic | global clock line |
| addr_i | in | std_ulogic_vector(31 downto 0) | address |
| rden_i | in | std_ulogic | read enable |
| wren_i | in | std_ulogic | write enable |
| data_i | in | std_ulogic_vector(31 downto 0) | data in |
| data_o | out | std_ulogic_vector(31 downto 0) | data out |
| ack_o | out | std_ulogic | transfer acknowledge |
| clkgen_en_o | out | std_ulogic | enable clock generator |
| clkgen_i | in | std_ulogic_vector(07 downto 0) | |
| spi_sck_o | out | std_ulogic | SPI serial clock |
| spi_sdo_o | out | std_ulogic | controller data out, peripheral data in |
| spi_sdi_i | in | std_ulogic | controller data in, peripheral data out |
| spi_csn_o | out | std_ulogic_vector(07 downto 0) | SPI CS |
| irq_o | out | std_ulogic | transmission done interrupt |
Signals
| Name | Type | Description |
|---|---|---|
| acc_en | std_ulogic | module access enable |
| addr | std_ulogic_vector(31 downto 0) | access address |
| wren | std_ulogic | word write enable |
| rden | std_ulogic | read enable |
| ctrl | std_ulogic_vector(14 downto 0) | accessible regs -- |
| tx_data_reg | std_ulogic_vector(31 downto 0) | |
| rx_data | std_ulogic_vector(31 downto 0) | |
| spi_clk | std_ulogic | clock generator -- |
| spi_start | std_ulogic | spi transceiver -- |
| spi_busy | std_ulogic | |
| spi_state0 | std_ulogic | |
| spi_state1 | std_ulogic | |
| spi_rtx_sreg | std_ulogic_vector(31 downto 0) | |
| spi_rx_data | std_ulogic_vector(31 downto 0) | |
| spi_bitcnt | std_ulogic_vector(05 downto 0) | |
| spi_bitcnt_max | std_ulogic_vector(05 downto 0) | |
| spi_sdi_ff0 | std_ulogic | |
| spi_sdi_ff1 | std_ulogic |
Constants
| Name | Type | Value | Description |
|---|---|---|---|
| hi_abb_c | natural | index_size_f(io_size_c)-1 | high address boundary bit |
| lo_abb_c | natural | index_size_f(spi_size_c) | low address boundary bit |
| ctrl_spi_cs0_c | natural | 0 | r/w: spi CS 0 |
| ctrl_spi_cs1_c | natural | 1 | r/w: spi CS 1 |
| ctrl_spi_cs2_c | natural | 2 | r/w: spi CS 2 |
| ctrl_spi_cs3_c | natural | 3 | r/w: spi CS 3 |
| ctrl_spi_cs4_c | natural | 4 | r/w: spi CS 4 |
| ctrl_spi_cs5_c | natural | 5 | r/w: spi CS 5 |
| ctrl_spi_cs6_c | natural | 6 | r/w: spi CS 6 |
| ctrl_spi_cs7_c | natural | 7 | r/w: spi CS 7 |
| ctrl_spi_en_c | natural | 8 | r/w: spi enable |
| ctrl_spi_cpha_c | natural | 9 | r/w: spi clock phase |
| ctrl_spi_prsc0_c | natural | 10 | r/w: spi prescaler select bit 0 |
| ctrl_spi_prsc1_c | natural | 11 | r/w: spi prescaler select bit 1 |
| ctrl_spi_prsc2_c | natural | 12 | r/w: spi prescaler select bit 2 |
| ctrl_spi_size0_c | natural | 13 | r/w: data size (00: 8-bit, 01: 16-bit) |
| ctrl_spi_size1_c | natural | 14 | r/w: data size (10: 24-bit, 11: 32-bit) |
| ctrl_spi_busy_c | natural | 31 | r/-: spi transceiver is busy |
Processes
- rw_access: ( clk_i )
Description
Read/Write Access ---------------------------------------------------------------------- -------------------------------------------------------------------------------------------
- spi_rtx_unit: ( clk_i )
Description
SPI Transceiver ------------------------------------------------------------------------ -------------------------------------------------------------------------------------------
- data_size: ( ctrl )
Description
RTX Data size ------------------------------------------------------------------------ -------------------------------------------------------------------------------------------
- rx_mapping: ( ctrl, spi_rtx_sreg )
Description
RX-Data Masking ------------------------------------------------------------------------ -------------------------------------------------------------------------------------------