clk: in std_logic; --input clk
adc_reset: in std_logic;
adc_miso: in std_logic; --spi master in slave out
- adc_channels: out std_logic_vector (35 downto 0); --consistent data of 3 channels
+ adc_channels: out std_logic_vector (71 downto 0); --consistent data of 3 channels
adc_sclk: out std_logic; --spi clk
adc_scs: out std_logic; --spi slave select
- adc_mosi: out std_logic --spi master out slave in
+ adc_mosi: out std_logic; --spi master out slave in
+ measur_count: out std_logic_vector(8 downto 0) --number of accumulated measurments
);
end adc_reader;
signal adc_data: std_logic_vector(11 downto 0);
signal adc_rst_old : std_logic_vector(1 downto 0);
- signal adc_address: std_logic_vector(8 downto 0);
-
+ signal adc_address: std_logic_vector(2 downto 0);
+ signal cumul_data: std_logic_vector(71 downto 0); --unconsistent data, containing different amounts of measurments
+ signal prepared_data: std_logic_vector(71 downto 0); --consistent data, waiting for clk sync to propagate to output
+ signal m_count_sig: std_logic_vector(8 downto 0); --measurments count waiting for clk to propagate to output
+ signal first_pass: std_logic;
begin
process
- variable data_ready : std_logic;
variable channel: channel_type;
variable reset_re: std_logic:='0';
- variable reset_count: integer:=0;
+ variable reset_count: std_logic_vector (3 downto 0);
begin
wait until (clk'event and clk='1');
- --reset rising edge detection
+ --rising edge detection of reset signal
adc_rst_old(0)<=adc_reset;
adc_rst_old(1)<=adc_rst_old(0);
case state is
when reset=>
- reset_re:='0'; --clear reset flag
- adc_scs<='1'; --active-low SS
- adc_sclk<='0'; --lower clock
- data_ready:='0';
- --addresse are CH(A2,A1,A0): CH0:(0,0,1),CH1:(1,0,1),CH2:(0,1,0)
- adc_address<="001101010";
- channel:=ch0;
- adc_channels(35 downto 0)<=(others=>'1'); --for debug only - remove this line!
- adc_data(11 downto 0)<=(others=>'1');
- reset_count:=0;
+ reset_re:='0'; --clear reset flag
+ adc_scs<='1'; --active-low SS
+ adc_sclk<='0'; --lower clock
+ first_pass<='1'; --mark data as unprepared
+ channel:=ch0; --prepare channel0
+ adc_data<=(others=>'0'); --null working data
+ cumul_data<=(others=>'0'); --null working data
+ prepared_data<=(others=>'0'); --null the output
+ adc_channels<=(others=>'0'); --null the output
+ measur_count<=(others=>'0'); --null the count
+ m_count_sig<=(others=>'0'); --null the count
+ adc_address<="001"; --set its address
+ reset_count:="0000";
state<=rst_wait;
when rst_wait=>
- if (reset_count<10) then
- reset_count:=reset_count+1;
- if (reset_count=7) then
- adc_scs<='0'; --give the adc some time to prepare before trensfer
- end if;
+ if (reset_count/="1111") then
+ reset_count:=std_logic_vector(unsigned(reset_count)+1);
+ --give the adc some time to prepare before transfer
+ adc_scs<=not reset_count(3);
else
state<=f1;
end if;
state<=f2;
when f2=> --2nd falling edge
adc_sclk<='0';
- adc_mosi<=adc_address(8); --A2 address
+ adc_mosi<=adc_address(2); --A2 address
state<=r2;
when r2=> --2nd rising edge (adc gets A2 address)
adc_sclk<='1';
state<=f3;
when f3=> --3rd falling edge
adc_sclk<='0';
- adc_mosi<=adc_address(7); --A1 address
+ adc_mosi<=adc_address(1); --A1 address
state<=r3;
when r3=> --rising edge
adc_sclk<='1';
state<=f4;
when f4=> --4th falling edge
adc_sclk<='0';
- adc_mosi<=adc_address(6); --A0 address
- --shift the addresses
- adc_address(8 downto 0)<=adc_address(5 downto 0) & adc_address(8 downto 6);
+ adc_mosi<=adc_address(0); --A0 address
state<=r4;
when r4=> --rising edge
adc_sclk<='1';
state<=r7;
when r7=> --7th rising edge, data ready
adc_sclk<='1';
- if (data_ready='1') then
+ if (first_pass='0') then
+ --add the current current to sum and shift the register
+ cumul_data(71 downto 0)<=
+ std_logic_vector(unsigned(cumul_data(47 downto 24))
+ +unsigned(adc_data(11 downto 0)))
+ & cumul_data(23 downto 0)
+ & cumul_data(71 downto 48);
+ end if;
+ state<=f8;
+ when f8=> --8th falling edge
+ adc_sclk<='0';
+ adc_mosi<='0'; --PD0
+ if (first_pass='0') then
case channel is
when ch0=>
- adc_channels(35 downto 24)<=adc_data(11 downto 0);
- --adc_channels(35 downto 24)<=(others=>'0');
- channel:=ch1;
+ adc_address<="101"; --ch1 address
+ channel:=ch1; --next channel code
when ch1=>
- adc_channels(23 downto 12)<=adc_data(11 downto 0);
- --adc_channels(23 downto 12)<=(others=>'1');
- channel:=ch2;
+ adc_address<="010"; --ch2 address
+ channel:=ch2; --next channel code
when ch2=>
- adc_channels(11 downto 0)<=adc_data(11 downto 0);
- --adc_channels(11 downto 0)<=(others=>'0');
- channel:=ch0;
+ --data order schould be: ch2 downto ch0 downto ch1
+ prepared_data(71 downto 0)<=cumul_data(71 downto 0);
+ m_count_sig<=std_logic_vector(unsigned(m_count_sig)+1);
+ adc_address<="001"; --ch0 address
+ channel:=ch0; --next channel code
end case;
end if;
- data_ready:='1';
- state<=f8;
- when f8=> --8th falling edge
- adc_sclk<='0';
- adc_mosi<='0'; --PD0
state<=r8;
- when r8=> --8th rising edge (adc gets PD0)
+ when r8=> --8th rising edge (adc gets PD0), we propagate our results to output
adc_sclk<='1';
+ adc_channels <= prepared_data; --data
+ measur_count <= m_count_sig; --count of measurments
+ first_pass<='0'; --data in next cycle are usable
state<=f9;
when f9=> --9th falling edge busy state between conversion (we write nothing)
adc_sclk<='0';
when f10=> --10th falling edge
adc_sclk<='0';
state<=r10;
- when r10=> --10th rising edge (we read 1. bit of conversion)
+ when r10=> --10th rising edge (we read 1. bit of new conversion)
adc_sclk<='1';
adc_data(11)<=adc_miso;
state<=f11;
state<=f15;
when f15=>
adc_sclk<='0';
- --for rising edge detection in next cycle
state<=r15;
when r15=> --15th rising edge
adc_sclk<='1';
projects / fpga / rpi-motor-control.git / blobdiff