);
end component;
- type state_type is (f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f11,f12,f13,f14,r1,r2,r3,r4,r5,r6,r7,r8,r9,r10,r11,r12,r13,r14,reset);
+ type state_type is (f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f11,f12,f13,f14,r1,r2,r3,r4,r5,r6,r7,r8,r9,r10,r11,r12,r13,r14,f15,r15,reset,rst_wait);
signal state : state_type;
type channel_type is (ch0, ch1, ch2);
process
variable data_ready : std_logic;
variable channel: channel_type;
+ variable reset_re: std_logic:='0';
+ variable reset_count: integer:=0;
begin
wait until (gpio_clk'event and gpio_clk='1');
+
+ --reset rising edge detection
+ adc_rst_old(0)<=adc_reset;
+ adc_rst_old(1)<=adc_rst_old(0);
+
+ if (adc_rst_old="01") then
+ reset_re:='1';
+ end if;
+
case state is
when reset=>
- adc_scs<='1'; --active-high SS
- data_ready:='0';
+ 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;
- when f1=>
- adc_scs<='0'; --active-high SS
+ adc_channels(35 downto 0)<=(others=>'1'); --for debug only - remove this line!
+ adc_data(11 downto 0)<=(others=>'1');
+ reset_count:=0;
+ 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;
+ else
+ state<=f1;
+ end if;
+ when f1=> --1st 'fallin edge' - its not falling edge in any case-if rst clock is low before
adc_sclk<='0'; --clk
adc_mosi<='1'; --start bit
state<=r1; --next state
- when r1=> --rising edge
- adc_sclk<='1';
+ when r1=> --1st rising edge (adc gets the start bit, we get date..)
+ adc_sclk<='1';
adc_data(5)<=adc_miso;
state<=f2;
when f2=> --2nd falling edge
adc_sclk<='0';
adc_mosi<=adc_address(8); --A2 address
state<=r2;
- when r2=> --rising edge
+ when r2=> --2nd rising edge (adc gets A2 address)
adc_sclk<='1';
adc_data(4)<=adc_miso;
state<=f3;
- when f3=> --3rd falling edge
+ when f3=> --3rd falling edge
adc_sclk<='0';
adc_mosi<=adc_address(7); --A1 address
state<=r3;
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_address(8 downto 0)<=adc_address(5 downto 0) & adc_address(8 downto 6);
state<=r4;
when r4=> --rising edge
adc_sclk<='1';
adc_sclk<='0';
adc_mosi<='1'; --SGL/DIF (HIGH - SGL=Single Ended)
state<=r6;
- when r6=> --rising edge
+ when r6=> --6th rising edge (we read last bit of conversion, adc gets SGL/DIF)
adc_sclk<='1';
adc_data(0)<=adc_miso;
state<=f7;
adc_sclk<='0';
adc_mosi<='0'; --PD1 (power down - PD1=PD0=0 -> power down between conversion)
state<=r7;
- when r7=> --rising edge, data ready
+ when r7=> --7th rising edge, data ready
adc_sclk<='1';
if (data_ready='1') then
case channel is
when ch0=>
- --adc_channels(35 downto 24)<=adc_data(11 downto 0);
- adc_channels(35 downto 24)<=(others=>'0');
+ adc_channels(35 downto 24)<=adc_data(11 downto 0);
+ --adc_channels(35 downto 24)<=(others=>'0');
channel:=ch1;
when ch1=>
- --adc_channels(23 downto 12)<=adc_data(11 downto 0);
- adc_channels(23 downto 12)<=(others=>'1');
+ adc_channels(23 downto 12)<=adc_data(11 downto 0);
+ --adc_channels(23 downto 12)<=(others=>'1');
channel:=ch2;
when ch2=>
- --adc_channels(11 downto 0)<=adc_data(11 downto 0);
- adc_channels(11 downto 0)<=(others=>'0');
+ adc_channels(11 downto 0)<=adc_data(11 downto 0);
+ --adc_channels(11 downto 0)<=(others=>'0');
channel:=ch0;
end case;
end if;
adc_sclk<='0';
adc_mosi<='0'; --PD0
state<=r8;
- when r8=> --rising edge
+ when r8=> --8th rising edge (adc gets PD0)
adc_sclk<='1';
state<=f9;
- when f9=> --busy state between conversion, 9th falling edge
+ when f9=> --9th falling edge busy state between conversion (we write nothing)
adc_sclk<='0';
state<=r9;
- when r9=> --10th rising edge
+ when r9=> --9th rising edge (we nor ads get nothing)
adc_sclk<='1';
- adc_data(11)<=adc_miso;
state<=f10;
- when f10=>
+ when f10=> --10th falling edge
adc_sclk<='0';
state<=r10;
- when r10=> --11th rising edge
+ when r10=> --10th rising edge (we read 1. bit of conversion)
adc_sclk<='1';
- adc_data(10)<=adc_miso;
+ adc_data(11)<=adc_miso;
state<=f11;
when f11=>
adc_sclk<='0';
state<=r11;
- when r11=> --12th rising edge
+ when r11=> --11th rising edge
adc_sclk<='1';
- adc_data(9)<=adc_miso;
+ adc_data(10)<=adc_miso;
state<=f12;
when f12=>
adc_sclk<='0';
state<=r12;
- when r12=> --13th rising edge
+ when r12=> --12th rising edge
adc_sclk<='1';
- adc_data(8)<=adc_miso;
+ adc_data(9)<=adc_miso;
state<=f13;
when f13=>
adc_sclk<='0';
state<=r13;
- when r13=> --14th rising edge
+ when r13=> --13th rising edge
adc_sclk<='1';
- adc_data(7)<=adc_miso;
+ adc_data(8)<=adc_miso;
state<=f14;
when f14=>
adc_sclk<='0';
- --for rising edge detection in next cycle
- adc_rst_old(0)<=adc_reset;
- adc_rst_old(1)<=adc_rst_old(0);
state<=r14;
- when r14=> --15th rising edge
+ when r14=> --14th rising edge
+ adc_sclk<='1';
+ adc_data(7)<=adc_miso;
+ state<=f15;
+ when f15=>
+ adc_sclk<='0';
+ --for rising edge detection in next cycle
+ state<=r15;
+ when r15=> --15th rising edge
adc_sclk<='1';
adc_data(6)<=adc_miso;
- if (adc_rst_old="01") then --we check rising edge of reset
+ if (reset_re='1') then --we check rising edge of reset
state<=reset;
else
state<=f1;
projects / fpga / rpi-motor-control.git / commitdiff