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ibm4704_usb: Fix interrupt of clock(rising edge)

tags/v2.9
tmk 9 years ago
parent
6014d1014e
commit
9a2282157f
3 changed files with 23 additions and 26 deletions
Split View Show Diff Stats
  1. 2
    2
      converter/ibm4704_usb/config.h
  2. 3
    3
      converter/ibm4704_usb/ibm4704.txt
  3. 18
    21
      tmk_core/protocol/ibm4704.c

+ 2
- 2
converter/ibm4704_usb/config.h View File

@@ -51,8 +51,8 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
#define IBM4704_DATA_DDR DDRD
#define IBM4704_DATA_BIT 0

/* Pin interrupt on rising edge */
#define IBM4704_INT_INIT() do { EICRA |= ((1<<ISC11)|(0<<ISC10)); } while (0)
/* Pin interrupt on rising edge of clock */
#define IBM4704_INT_INIT() do { EICRA |= ((1<<ISC11)|(1<<ISC10)); } while (0)
#define IBM4704_INT_ON() do { EIMSK |= (1<<INT1); } while (0)
#define IBM4704_INT_OFF() do { EIMSK &= ~(1<<INT1); } while (0)
#define IBM4704_INT_VECT INT1_vect

+ 3
- 3
converter/ibm4704_usb/ibm4704.txt View File

@@ -57,15 +57,15 @@ Keyboard to Host
----------------
Data bits are LSB first and Pairty is odd. Clock has around 60us high and 30us low part.

____ __ __ __ __ __ __ __ __ __ ________
Clock \____/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/
____ __ __ __ __ __ __ __ __ __ _______
Clock \_____/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/
____ ____ ____ ____ ____ ____ ____ ____ ____ ____
Data ____/ X____X____X____X____X____X____X____X____X____X________
Start 0 1 2 3 4 5 6 7 P Stop

Start bit: can be long as 300-350us.
Inhibit: Pull Data line down to inhibit keyboard to send.
Timing: Host reads bit while Clock is hi.
Timing: Host reads bit while Clock is hi.(rising edge)
Stop bit: Keyboard pulls down Data line to lo after 9th clock.



+ 18
- 21
tmk_core/protocol/ibm4704.c View File

@@ -104,50 +104,47 @@ uint8_t ibm4704_recv_response(void)
return rbuf_dequeue();
}

uint8_t ibm4704_recv(void)
{
if (rbuf_has_data()) {
return rbuf_dequeue();
} else {
return -1;
}
}

/*
Keyboard to Host
----------------
Data bits are LSB first and Parity is odd. Clock has around 60us high and 30us low part.

____ __ __ __ __ __ __ __ __ __ ________
Clock \____/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/
____ __ __ __ __ __ __ __ __ __ _______
Clock \_____/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/
____ ____ ____ ____ ____ ____ ____ ____ ____ ____
Data ____/ X____X____X____X____X____X____X____X____X____X________
Start 0 1 2 3 4 5 6 7 P Stop

Start bit: can be long as 300-350us.
Inhibit: Pull Data line down to inhibit keyboard to send.
Timing: Host reads bit while Clock is hi.
Timing: Host reads bit while Clock is hi.(rising edge)
Stop bit: Keyboard pulls down Data line to lo after 9th clock.
*/
uint8_t ibm4704_recv(void)
{
if (rbuf_has_data()) {
return rbuf_dequeue();
} else {
return -1;
}
}

ISR(IBM4704_INT_VECT)
{
static enum {
INIT, START, BIT0, BIT1, BIT2, BIT3, BIT4, BIT5, BIT6, BIT7, PARITY,
} state = INIT;
STOP, BIT0, BIT1, BIT2, BIT3, BIT4, BIT5, BIT6, BIT7, PARITY
} state = STOP;
// LSB first
static uint8_t data = 0;
// Odd parity
static uint8_t parity = false;

ibm4704_error = 0;
// return unless falling edge
if (clock_in()) { goto RETURN; } // why this occurs?

state++;
switch (state) {
case START:
switch (state++) {
case STOP:
// Data:Low
WAIT(data_hi, 10, state);
WAIT(data_lo, 10, state);
break;
case BIT0:
case BIT1:
@@ -182,7 +179,7 @@ ERROR:
while (ibm4704_send(0xFE)) _delay_ms(1); // resend
xprintf("R:%02X%02X\n", state, data);
DONE:
state = INIT;
state = STOP;
data = 0;
parity = false;
RETURN:

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