From 88f18d98a1847e0911949891084b2c2156b3a9c2 Mon Sep 17 00:00:00 2001
From: type-two <minimus.hargroove@gmail.com>
Date: Fri, 4 Sep 2026 11:19:17 +1000
Subject: [PATCH] =?UTF-8?q?fix(urovo):=20status()=20falls=20back=20to=20ES?=
 =?UTF-8?q?C=20!S=20=E2=80=94=20firmware=20stops=20answering=20ESC=20!=3F?=
 =?UTF-8?q?=20after=20&CALIBRATE,A,R?=
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Content-Transfer-Encoding: 8bit

After &CALIBRATE,A,R this printer answered model() but not the one-byte <ESC>!?
status, for minutes, so wait_ready/recover/do_print all reported 'no response'
and refused to print a printer that was in fact Ready. The extended <ESC>!S is
still answered: STX + 4 bytes + ETX CRLF, first byte 0x40+code, which maps
one-to-one onto STATUS_TEXT (0x48 = ribbon latched, 0x40 = Ready). Seen live:
!? silent, !S -> 02 40 40 40 40 03 0D 0A.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
---
 mac/urovo.py | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/mac/urovo.py b/mac/urovo.py
index 0263559..be471a6 100644
--- a/mac/urovo.py
+++ b/mac/urovo.py
@@ -147,11 +147,28 @@ class Urovo(object):
 
     # ---- status ----------------------------------------------------------
     def status(self, wait=0.8):
-        """Real-time status: <ESC>!? -> one byte. 0x00 = Ready."""
+        """Real-time status. 0x00 = Ready.
+
+        Asks the one-byte <ESC>!? first. After &CALIBRATE,A,R this firmware stops answering
+        that form entirely -- the printer sat "no response" for minutes while model() kept
+        working over the same pipe -- and every caller that gates on status() (wait_ready,
+        recover, do_print) then refuses to print a printer that is in fact fine. So fall back to
+        the extended <ESC>!S, which it does keep answering: STX + 4 status bytes + ETX CR LF,
+        first byte 0x40 + code. That offset maps one-to-one onto STATUS_TEXT (0x41 head open,
+        0x48 ribbon latched, 0x40 ready), so the fallback returns the same codes as the primary.
+        Seen live: <ESC>!? silent, <ESC>!S -> 02 40 40 40 40 03 0D 0A = Ready."""
         self.flush_in()
         self.write(b'\x1b!?')
         r = self.read(wait)
-        return r[-1] if r else None
+        if r:
+            return r[-1]
+        self.flush_in()
+        self.write(b'\x1b!S')
+        r = self.read(wait)
+        i = r.find(b'\x02') if r else -1
+        if i >= 0 and len(r) > i + 1:
+            return (r[i + 1] - 0x40) & 0xFF
+        return None
 
     def model(self):
         self.flush_in()