diff options
| author | Paul Selkirk <pselkirk@isc.org> | 2014-09-11 13:56:42 -0400 |
|---|---|---|
| committer | Paul Selkirk <pselkirk@isc.org> | 2014-09-11 13:56:42 -0400 |
| commit | 595a3e72b4e2c166cc978e59c025560353df0a6b (patch) | |
| tree | 325fbbc0988f754786c6a8d49049616196e72c4f /src/rtl | |
| parent | a768072bbe3ea9762ee3325ffb5c42c3156e7859 (diff) | |
correct size of I2C FSM state values
When adding new I2C states, I neglected to update the size of all the
state parameter values, so e.g. I2C_WAITSTOP = 14'b1 << 15;
This overflows to 0, which manifests as the I2C bus hanging when asked
to access an unsupported device address.
Diffstat (limited to 'src/rtl')
| -rw-r--r-- | src/rtl/i2c_core.v | 49 |
1 files changed, 22 insertions, 27 deletions
diff --git a/src/rtl/i2c_core.v b/src/rtl/i2c_core.v index a026545..f5d7c87 100644 --- a/src/rtl/i2c_core.v +++ b/src/rtl/i2c_core.v @@ -80,22 +80,22 @@ module i2c_core ( //////////////// ///// protocol-level state machine //////////////// - parameter I2C_START = 14'b1 << 0; // should only pass through this state for one cycle - parameter I2C_RESTART = 14'b1 << 1; - parameter I2C_DADDR = 14'b1 << 2; - parameter I2C_ACK_DADDR = 14'b1 << 3; - parameter I2C_WR_DATA = 14'b1 << 4; - parameter I2C_RXD_SYN = 14'b1 << 5; - parameter I2C_RXD_ACK = 14'b1 << 6; - parameter I2C_ACK_WR = 14'b1 << 7; - parameter I2C_END_WR = 14'b1 << 8; - parameter I2C_TXD_SYN = 14'b1 << 9; - parameter I2C_TXD_ACK = 14'b1 << 10; - parameter I2C_RD_DATA = 14'b1 << 11; - parameter I2C_ACK_RD = 14'b1 << 12; - parameter I2C_END_RD = 14'b1 << 13; - parameter I2C_END_RD2 = 14'b1 << 14; - parameter I2C_WAITSTOP = 14'b1 << 15; + parameter I2C_START = 16'b1 << 0; // should only pass through this state for one cycle + parameter I2C_RESTART = 16'b1 << 1; + parameter I2C_DADDR = 16'b1 << 2; + parameter I2C_ACK_DADDR = 16'b1 << 3; + parameter I2C_WR_DATA = 16'b1 << 4; + parameter I2C_ACK_WR = 16'b1 << 5; + parameter I2C_END_WR = 16'b1 << 6; + parameter I2C_RD_DATA = 16'b1 << 7; + parameter I2C_ACK_RD = 16'b1 << 8; + parameter I2C_END_RD = 16'b1 << 9; + parameter I2C_END_RD2 = 16'b1 << 10; + parameter I2C_WAITSTOP = 16'b1 << 11; + parameter I2C_RXD_SYN = 16'b1 << 12; + parameter I2C_RXD_ACK = 16'b1 << 13; + parameter I2C_TXD_SYN = 16'b1 << 14; + parameter I2C_TXD_ACK = 16'b1 << 15; parameter I2C_nSTATES = 16; @@ -304,9 +304,7 @@ module i2c_core ( end I2C_RXD_ACK: begin // wait for coretest ack if (rxd_ack) - begin - rxd_syn_reg <= 0; - end + rxd_syn_reg <= 0; end I2C_ACK_WR: begin SDA_pd <= 1'b1; // active pull down ACK @@ -325,17 +323,14 @@ module i2c_core ( // read branch I2C_TXD_SYN: begin // get data from the coretest bus - if (txd_syn) - begin - I2C_rdata <= txd_data; - txd_ack_reg <= 1; - end + if (txd_syn) begin + I2C_rdata <= txd_data; + txd_ack_reg <= 1; + end end I2C_TXD_ACK: begin // send coretest ack if (!txd_syn) - begin - txd_ack_reg <= 0; - end + txd_ack_reg <= 0; end I2C_RD_DATA: begin // shift out data on falling edges of clock SDA_pd <= I2C_rdata[7] ? 1'b0 : 1'b1; |