From: tmk <hasu@tmk-kbd.com>
Date: Wed, 13 May 2020 14:34:42 +0000 (+0900)
Subject: ibmpc: Add Z-150 AT protocol recognition
X-Git-Url: https://git.friedersdorff.com/?a=commitdiff_plain;h=f80601db962384146eb80705aaa3057a1b3848b4;p=max%2Ftmk_keyboard.git

ibmpc: Add Z-150 AT protocol recognition

https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#zenith-z-150-beige
---

diff --git a/tmk_core/protocol/ibmpc.c b/tmk_core/protocol/ibmpc.c
index a071db19..e84548c6 100644
--- a/tmk_core/protocol/ibmpc.c
+++ b/tmk_core/protocol/ibmpc.c
@@ -359,12 +359,17 @@ ISR(IBMPC_INT_VECT)
         case 0b01010000:
         case 0b11010000:
             // AT-done
-            // DO NOT check stop bit. Zenith Z-150(AT) asserts stop bit as low for no reason.
-            // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#zenith-z-150-beige
             // TODO: parity check?
             ibmpc_isr_debug = isr_state;
+            // stop bit check
+            if (isr_state & 0x8000) {
+                ibmpc_protocol = IBMPC_PROTOCOL_AT;
+            } else {
+                // Zenith Z-150 AT(beige/white lable) asserts stop bit as low
+                // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#zenith-z-150-beige
+                ibmpc_protocol = IBMPC_PROTOCOL_AT_Z150;
+            }
             isr_state = isr_state>>6;
-            ibmpc_protocol = IBMPC_PROTOCOL_AT;
             goto DONE;
             break;
         case 0b01100000:
diff --git a/tmk_core/protocol/ibmpc.h b/tmk_core/protocol/ibmpc.h
index c994ddb6..4f682aa7 100644
--- a/tmk_core/protocol/ibmpc.h
+++ b/tmk_core/protocol/ibmpc.h
@@ -72,6 +72,7 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #define IBMPC_PROTOCOL_NO       0
 #define IBMPC_PROTOCOL_AT       0x10
+#define IBMPC_PROTOCOL_AT_Z150  0x11
 #define IBMPC_PROTOCOL_XT       0x20
 #define IBMPC_PROTOCOL_XT_IBM   0x21
 #define IBMPC_PROTOCOL_XT_CLONE 0x22