max/tmk_keyboard
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ibmpc: Fix stop bit check code in ISR

Browse source 
removing function call makes prologue/epilogue shorter
This commit is contained in:
tmk 2020-01-24 00:44:27 +09:00
parent a42cc4bddb
commit e89ade52e1
1 changed files with 19 additions and 10 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

29
tmk_core/protocol/ibmpc.c
View file

@ -191,6 +191,8 @@ int16_t ibmpc_host_recv_response(void)
return data;
}
// NOTE: to read data line early as possible:
// write naked ISR with asembly code to read the line and call C func to do other job?
ISR(IBMPC_INT_VECT)
{
uint8_t dbit;
@ -240,16 +242,23 @@ ISR(IBMPC_INT_VECT)
goto DONE;
break;
case 0b10100000:
// XT IBM-done or AT-midway
// wait and check for clock of AT stop bit
if (wait_clock_hi(100) && wait_clock_lo(100)) { // FIXME this makes ISR prologe long
// AT-midway
return;
} else {
// XT-IBM-done
recv_data = (isr_data>>8) & 0xFF;
goto DONE;
}
{
uint8_t us = 150;
// wait for rising and falling edge of AT stop bit
while (!(IBMPC_CLOCK_PIN&(1<<IBMPC_CLOCK_BIT)) && us) { wait_us(1); us--; }
while ( IBMPC_CLOCK_PIN&(1<<IBMPC_CLOCK_BIT) && us) { wait_us(1); us--; }
if (us) {
// found stop bit: return immediately and process the stop bit in ISR
// AT-midway
return;
} else {
// no stop bit
// XT-IBM-done
recv_data = (isr_data>>8) & 0xFF;
goto DONE;
}
}
break;
case 0b00010000:
case 0b10010000: