Entity: neorv32_pwm
- File: neorv32_pwm.vhd
Diagram
Description
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<< NEORV32 - Pulse Width Modulation Controller (PWM) >>
*
Simple PWM controller with 8 bit resolution for the duty cycle and programmable base
frequency. The controller supports up to 60 PWM channels.
*
BSD 3-Clause License
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Copyright (c) 2021, Stephan Nolting. All rights reserved.
#
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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Generics
| Generic name | Type | Value | Description |
|---|---|---|---|
| NUM_CHANNELS | natural | number of PWM channels (0..60) |
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) | |
| pwm_o | out | std_ulogic_vector(NUM_CHANNELS-1 downto 0) | pwm output channels -- |
Signals
| Name | Type | Description |
|---|---|---|
| acc_en | std_ulogic | module access enable |
| addr | std_ulogic_vector(31 downto 0) | access address |
| wren | std_ulogic | write enable |
| rden | std_ulogic | read enable |
| pwm_ch | pwm_ch_t | duty cycle (r/w) |
| enable | std_ulogic | enable unit (r/w) |
| prsc | std_ulogic_vector(2 downto 0) | clock prescaler (r/w) |
| pwm_ch_rd | pwm_ch_rd_t | duty cycle read-back |
| prsc_tick | std_ulogic | prescaler clock generator -- |
| pwm_cnt | std_ulogic_vector(7 downto 0) | pwm core counter -- |
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(pwm_size_c) | low address boundary bit |
| ctrl_enable_c | natural | 0 | r/w: PWM enable |
| ctrl_prsc0_bit_c | natural | 1 | r/w: prescaler select bit 0 |
| ctrl_prsc1_bit_c | natural | 2 | r/w: prescaler select bit 1 |
| ctrl_prsc2_bit_c | natural | 3 | r/w: prescaler select bit 2 |
Types
| Name | Type | Description |
|---|---|---|
| pwm_ch_t | accessible regs -- | |
| pwm_ch_rd_t |
Processes
- wr_access: ( clk_i )
Description
Write access --------------------------------------------------------------------------- -------------------------------------------------------------------------------------------
- pwm_dc_rd_gen: ( pwm_ch )
Description
duty cycle read-back --
- pwm_core: ( clk_i )
Description
PWM Core ------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------