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Code Issues Releases Wiki Activity

[Archie] FDC fixes

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This commit is contained in:
Gyorgy Szombathelyi
2019-03-03 14:51:45 +01:00
parent 1d60379857
commit b6c3910709
1 changed files with 35 additions and 20 deletions
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55
cores/archie/rtl/fdc1772.v
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@@ -109,8 +109,13 @@ always @(posedge clkcpu)
wire irq_clr = !floppy_reset || cpu_read_status;
always @(posedge clkcpu or posedge irq_clr) begin
if(irq_clr) irq <= 1'b0;
else if(irq_set) irq <= 1'b1;
reg irq_setD;
if(irq_clr) irq <= 1'b0;
else begin
irq_setD <= irq_set;
if(~irq_setD & irq_set) irq <= 1'b1;
end
end
assign floppy_firq = irq;
@@ -345,18 +350,21 @@ wire step_busy = (step_rate_cnt != 0);
reg [7:0] step_to;
always @(posedge clkcpu) begin
reg data_transfer_can_start;
irq_set <= 0;
sd_card_read <= 0;
sd_card_write <= 0;
if(!floppy_reset) begin
motor_on <= 1'b0;
busy <= 1'b0;
step_in <= 1'b0;
step_out <= 1'b0;
irq_set <= 1'b0;
sd_card_read <= 0;
sd_card_write <= 0;
data_transfer_start <= 1'b0;
data_transfer_can_start <= 0;
end else if (clk8m_en) begin
sd_card_read <= 0;
sd_card_write <= 0;
irq_set <= 1'b0;
data_transfer_start <= 1'b0;
@@ -427,14 +435,15 @@ always @(posedge clkcpu) begin
end else begin
// read sector
if(cmd[7:5] == 3'b100) begin
if (sd_state == SD_IDLE && fifo_cpuptr == 0) sd_card_read <= 1;
if (fifo_cpuptr == 0) sd_card_read <= 1;
// we are busy until the right sector header passes under
// the head and the arm7 has delivered at least one byte
// (one byte is sufficient as the arm7 is much faster and
// all further bytes will arrive in time)
if(fd_ready && fd_sector_hdr &&
(fd_sector == sector) && (sd_buff_addr != 0))
data_transfer_start <= 1'b1;
// the head and the sd-card controller indicates the sector
// is in the fifo
if(sd_card_done) data_transfer_can_start <= 1;
if(fd_ready && fd_sector_hdr && (fd_sector == sector) && data_transfer_can_start) begin
data_transfer_can_start <= 0;
data_transfer_start <= 1;
end
if(data_transfer_done) begin
busy <= 1'b0;
@@ -447,7 +456,7 @@ always @(posedge clkcpu) begin
if(cmd[7:5] == 3'b101) begin
if (fifo_cpuptr == 0) data_transfer_start <= 1'b1;
if (data_transfer_done) sd_card_write <= 1;
if (sd_card_write_done) begin
if (sd_card_done) begin
busy <= 1'b0;
motor_timeout_index <= MOTOR_IDLE_COUNTER - 1;
irq_set <= 1'b1; // emit irq when command done
@@ -533,24 +542,28 @@ localparam SD_WRITE = 2;
reg [1:0] sd_state;
reg sd_card_write;
reg sd_card_read;
reg sd_card_write_done;
reg sd_card_done;
always @(posedge clkcpu) begin
reg sd_ackD;
reg sd_card_readD;
reg sd_card_writeD;
sd_card_readD <= sd_card_read;
sd_card_writeD <= sd_card_write;
sd_ackD <= sd_ack;
if (sd_ack) {sd_rd, sd_wr} <= 0;
if (clk8m_en) sd_card_write_done <= 0;
if (clk8m_en) sd_card_done <= 0;
case (sd_state)
SD_IDLE:
begin
s_odd <= 0;
if (sd_card_read) begin
if (~sd_card_readD & sd_card_read) begin
sd_rd <= ~{ floppy_drive[1], floppy_drive[0] };
sd_state <= SD_READ;
end
else if (sd_card_write) begin
else if (~sd_card_writeD & sd_card_write) begin
sd_wr <= ~{ floppy_drive[1], floppy_drive[0] };
sd_state <= SD_WRITE;
end
@@ -559,8 +572,10 @@ always @(posedge clkcpu) begin
SD_READ:
begin
if (sd_ackD & ~sd_ack) begin
if (s_odd) sd_state <= SD_IDLE;
else begin
if (s_odd) begin
sd_state <= SD_IDLE;
sd_card_done <= 1; // to be on the safe side now, can be issued earlier
end else begin
s_odd <= 1;
sd_rd <= ~{ floppy_drive[1], floppy_drive[0] };
end
@@ -572,7 +587,7 @@ always @(posedge clkcpu) begin
if (sd_ackD & ~sd_ack) begin
if (s_odd) begin
sd_state <= SD_IDLE;
sd_card_write_done <= 1;
sd_card_done <= 1;
end else begin
s_odd <= 1;
sd_wr <= ~{ floppy_drive[1], floppy_drive[0] };