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ibm4704_usb: Fix interrupt of clock(rising edge)

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tmk 2015-05-14 15:38:15 +09:00
parent 6014d1014e
commit 9a2282157f
3 changed files with 27 additions and 30 deletions
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47
tmk_core/protocol/ibm4704.c
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@ -104,22 +104,6 @@ uint8_t ibm4704_recv_response(void)
return rbuf_dequeue();
}
/*
Keyboard to Host
----------------
Data bits are LSB first and Parity is odd. Clock has around 60us high and 30us low part.
____ __ __ __ __ __ __ __ __ __ ________
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.
Stop bit: Keyboard pulls down Data line to lo after 9th clock.
*/
uint8_t ibm4704_recv(void)
{
if (rbuf_has_data()) {
@ -129,25 +113,38 @@ uint8_t ibm4704_recv(void)
}
}
/*
Keyboard to Host
----------------
Data bits are LSB first and Parity is odd. Clock has around 60us high and 30us low part.
____ __ __ __ __ __ __ __ __ __ _______
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.(rising edge)
Stop bit: Keyboard pulls down Data line to lo after 9th clock.
*/
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: