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

ibmpc: Add two-byte buffer for data received

Browse source
This commit is contained in:
tmk 2020-01-24 03:20:14 +09:00
parent e89ade52e1
commit 9acc900ffb
2 changed files with 61 additions and 53 deletions
Download patch file Download diff file Expand all files Collapse all files

76
tmk_core/protocol/ibmpc.c
View file

@ -42,7 +42,6 @@ POSSIBILITY OF SUCH DAMAGE.
#include <stdbool.h>
#include <avr/interrupt.h>
#include <util/atomic.h>
#include "ringbuf.h"
#include "ibmpc.h"
#include "debug.h"
#include "timer.h"
@ -57,18 +56,20 @@ POSSIBILITY OF SUCH DAMAGE.
} while (0)
#define BUF_SIZE 16
static uint8_t buf[BUF_SIZE];
static ringbuf_t rb = {
.buffer = buf,
.head = 0,
.tail = 0,
.size_mask = BUF_SIZE - 1
};
volatile uint8_t ibmpc_protocol = IBMPC_PROTOCOL_AT;
volatile uint8_t ibmpc_error = IBMPC_ERR_NONE;
/* 2-byte buffer for data received from keyhboard
* buffer states:
* FFFF: empty
* FFss: one data
* sstt: two data(full)
* 0xFF can not be stored as data in buffer because it means empty or no data.
*/
static volatile uint16_t recv_data = 0xFFFF;
/* internal state of receiving data */
static volatile uint16_t isr_data = 0x8000;
void ibmpc_host_init(void)
{
// initialize reset pin to HiZ
@ -142,7 +143,7 @@ int16_t ibmpc_host_send(uint8_t data)
WAIT(data_hi, 50, 9);
// clear buffer to get response correctly
ringbuf_reset(&rb);
recv_data = 0xFFFF;
ibmpc_host_isr_clear();
idle();
@ -156,27 +157,28 @@ ERROR:
}
/*
* Receive data from keyboard with ISR
* Receive data from keyboard
*/
static volatile int16_t recv_data = -1;
static volatile uint16_t isr_data = 0x8000;
void ibmpc_host_isr_clear(void)
{
isr_data = 0x8000;
}
int16_t ibmpc_host_recv(void)
{
int16_t data = 0;
uint16_t data = 0;
uint8_t ret = 0xFF;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
data = recv_data;
recv_data = -1;
if ((data&0xFF00) != 0xFF00) { // recv_data:sstt -> recv_data:FFtt, ret:ss
ret = (data>>8)&0x00FF;
recv_data = data | 0xFF00;
} else if (data != 0xFFFF) { // recv_data:FFss -> recv_data:FFFF, ret:ss
ret = data&0x00FF;
recv_data = data | 0x00FF;
}
}
if (data != -1) {
dprintf("r%04X ", data);
if (ret != 0xFF) {
dprintf("r%02X(%04X) ", ret, recv_data);
}
return data;
return ((ret != 0xFF) ? ret : -1);
}
@ -191,7 +193,14 @@ int16_t ibmpc_host_recv_response(void)
return data;
}
// NOTE: to read data line early as possible:
void ibmpc_host_isr_clear(void)
{
isr_data = 0x8000;
recv_data = 0xFFFF;
}
// NOTE: With this ISR data line can be read within 2us after clock falling edge.
// 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)
{
@ -200,7 +209,7 @@ ISR(IBMPC_INT_VECT)
isr_data = isr_data>>1;
if (dbit) isr_data |= 0x8000;
// isr_data:
// isr_data: state of receiving data from keyboard
// 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
// -----------------------------------------------------
// Initial: *1 0 0 0 0 0 0 0 | 0 0 0 0 0 0 0 0
@ -238,7 +247,8 @@ ISR(IBMPC_INT_VECT)
break;
case 0b11000000:
// XT Clone-done
recv_data = (isr_data>>8) & 0xFF;
recv_data = recv_data<<8;
recv_data |= (isr_data>>8) & 0xFF;
goto DONE;
break;
case 0b10100000:
@ -255,7 +265,8 @@ ISR(IBMPC_INT_VECT)
} else {
// no stop bit
// XT-IBM-done
recv_data = (isr_data>>8) & 0xFF;
recv_data = recv_data<<8;
recv_data |= (isr_data>>8) & 0xFF;
goto DONE;
}
}
@ -265,7 +276,8 @@ ISR(IBMPC_INT_VECT)
case 0b01010000:
case 0b11010000:
// AT-done
recv_data = (isr_data>>6) & 0xFF;
recv_data = recv_data<<8;
recv_data |= (isr_data>>6) & 0xFF;
goto DONE;
break;
case 0b01100000:
@ -279,7 +291,9 @@ ISR(IBMPC_INT_VECT)
break;
}
DONE:
// TODO: buffer for recv_data
// TODO: check protocol change to support keyboard howswap
// not correct if there is clock edge within short time like 100us after receving data
// TODO: process error code: 0x00(AT), 0xFF(XT) in particular
isr_data = 0x8000; // clear to next data
return;
}