if (code == -1) { id = 0xFFFF; goto DONE; } // XT or No keyboard
if (code != 0xFA) { id = 0xFFFE; goto DONE; } // Broken PS/2?
- code = read_wait(1000);
+ // ID takes 500ms max TechRef [8] 4-41
+ code = read_wait(500);
if (code == -1) { id = 0x0000; goto DONE; } // AT
id = (code & 0xFF)<<8;
- code = read_wait(1000);
+ code = read_wait(500);
id |= code & 0xFF;
DONE:
switch (state) {
case INIT:
+ xprintf("S%u\n", timer_read());
ibmpc_protocol = IBMPC_PROTOCOL_AT;
keyboard_kind = NONE;
keyboard_id = 0x0000;
- init_time = timer_read();
- xprintf("I%u\n", init_time);
- // re-initialize keyboard
+ matrix_clear();
+ clear_keyboard();
+
+ // Reset XT-initialize keyboard
// XT: hard reset 500ms for IBM XT Type-1 keyboard and clones
// XT: soft reset 20ms min(clock Lo)
ibmpc_host_disable(); // soft reset: inihibit(clock Lo/Data Hi)
IBMPC_RST_LO();
wait_ms(500);
IBMPC_RST_HIZ();
- ibmpc_host_enable(); // soft reset: idle(clock Hi/Data Hi)
-
- // TODO: should in while disabling interrupt?
- // clear ISR state after protocol recognition
ibmpc_host_isr_clear();
+ ibmpc_host_enable(); // soft reset: idle(clock Hi/Data Hi)
- matrix_clear();
- clear_keyboard();
+ init_time = timer_read();
+ xprintf("I%u\n", init_time);
state = WAIT_STARTUP;
break;
// For example, XT/AT sends 'AA' and Terminal sends 'AA BF BF' after BAT
// AT 84-key: POR and BAT can take 900-9900ms according to AT TechRef [8] 4-7
// AT 101/102-key: POR and BAT can take 450-2500ms according to AT TechRef [8] 4-39
- // 2) Read and ignore key input by user when signal handling/protocol error occurs
+ // 2) Read key typed by user after error on protocol or scan code
// This can happen in case of keyboard hotswap, unstable hardware, signal integrity problem or bug
if (ibmpc_host_recv() != -1 || timer_elapsed(init_time) > 10000) {
- // 500ms max wait for ID after AA TechRef [8] 4-41
- // 122-key Terminal 6110345: 1ms wait is enough
- wait_ms(100); ibmpc_host_recv();
- wait_ms(100); ibmpc_host_recv();
+ xprintf("W%u\n", timer_read());
+ // ID takes 500ms max? TechRef [8] 4-41, though, 1ms is enough for 122-key Terminal 6110345
+ read_wait(500); // for BF from Terminal
+ read_wait(500); // for BF from Terminal
state = READ_ID;
}
-
- // XT's 'AA' can not be handled correctly because protocol is configured as AT at this point.
- // TODO: Check ISR timeout error for XT AA?
break;
case READ_ID:
xprintf("R%u\n", timer_read());
ibmpc_protocol = IBMPC_PROTOCOL_AT;
}
- // clear ISR state after protocol recognition
- ibmpc_host_isr_clear();
-
state = LED_SET;
break;
case LED_SET:
#include <stdbool.h>
#include <avr/interrupt.h>
#include <util/atomic.h>
-#include "ringbuf.h"
#include "ibmpc.h"
#include "debug.h"
#include "timer.h"
} 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
WAIT(data_hi, 50, 9);
// clear buffer to get response correctly
- ringbuf_reset(&rb);
+ recv_data = 0xFFFF;
ibmpc_host_isr_clear();
idle();
}
/*
- * 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);
}
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)
{
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
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:
} 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;
}
}
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:
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;
}
projects / max / tmk_keyboard.git / commitdiff