srd: MX25Lxx05D: Decode status register bits.

[libsigrokdecode.git] / decoders / mx25lxx05d / mx25lxx05d.py

diff --git a/decoders/mx25lxx05d/mx25lxx05d.py b/decoders/mx25lxx05d/mx25lxx05d.py
index cb5472868f5606aa706b85b33ccc2dd552c15747..a5dab2ef39721f062855f36a0e0d39fe06af3378 100644 (file)
--- a/decoders/mx25lxx05d/mx25lxx05d.py
+++ b/decoders/mx25lxx05d/mx25lxx05d.py
@@ -93,6 +93,31 @@ device_name = {
     0x16: 'MX25L6405D',
 }
 
+def decode_status_reg(data):
+    # TODO: Additional per-bit(s) self.put() calls with correct start/end.
+
+    # Bits[0:0]: WIP (write in progress)
+    s = 'W' if (data & (1 << 0)) else 'No w'
+    ret = '%srite operation in progress.\n' % s
+
+    # Bits[1:1]: WEL (write enable latch)
+    s = '' if (data & (1 << 1)) else 'not '
+    ret += 'Internal write enable latch is %sset.\n' % s
+
+    # Bits[5:2]: Block protect bits
+    # TODO: More detailed decoding (chip-dependent).
+    ret += 'Block protection bits (BP3-BP0): 0x%x.\n' % ((data & 0x3c) >> 2)
+
+    # Bits[6:6]: Continuously program mode (CP mode)
+    s = '' if (data & (1 << 6)) else 'not '
+    ret += 'Device is %sin continuously program mode (CP mode).\n' % s
+
+    # Bits[7:7]: SRWD (status register write disable)
+    s = '' if (data & (1 << 7)) else 'not '
+    ret += 'Status register writes are %sallowed.\n' % s
+
+    return ret
+
 class Decoder(srd.Decoder):
     api_version = 1
     id = 'mx25lxx05d'
@@ -168,16 +193,13 @@ class Decoder(srd.Decoder):
             self.start_sample = self.ss
             self.putx([0, ['Command: %s' % cmds[self.cmd]]])
         elif self.cmdstate in (2, 3, 4):
-            # Bytes 2/3/4: Master sends address of the sector to erase.
-            # Note: Assumes SPI data is 8 bits wide (it is for MX25Lxx05D).
-            # TODO: LSB-first of MSB-first?
-            self.addr <<= 8
-            self.addr |= mosi
-            self.putx([0, ['Address byte %d: 0x%02x' % (self.cmdstate - 1,
-                        miso)]]) # TODO: Count from 0 or 1?
+            # Bytes 2/3/4: Master sends sectror address (24bits, MSB-first).
+            self.addr |= (mosi << ((4 - self.cmdstate) * 8))
+            # self.putx([0, ['Sector address, byte %d: 0x%02x' % \
+            #                (4 - self.cmdstate, mosi)]])
 
         if self.cmdstate == 4:
-            d = 'Erase sector %d' % self.addr
+            d = 'Erase sector %d (0x%06x)' % (self.addr, self.addr)
             self.put(self.start_sample, self.es, self.out_ann, [0, [d]])
             # TODO: Max. size depends on chip, check that too if possible.
             if self.addr % 4096 != 0:
@@ -238,7 +260,7 @@ class Decoder(srd.Decoder):
             # Bytes 2-x: Slave sends status register as long as master clocks.
             if self.cmdstate <= 3: # TODO: While CS# asserted.
                 self.putx([0, ['Status register: 0x%02x' % miso]])
-                # TODO: Decode status register bits.
+                self.putx([0, [decode_status_reg(miso)]])
 
             if self.cmdstate == 3: # TODO: If CS# got de-asserted.
                 self.state = IDLE
@@ -277,6 +299,37 @@ class Decoder(srd.Decoder):
 
         self.cmdstate += 1
 
+    def handle_read(self, mosi, miso):
+        # Read data bytes: Master asserts CS#, sends READ command, sends
+        # 3-byte address, reads >= 1 data bytes, de-asserts CS#.
+        if self.cmdstate == 1:
+            # Byte 1: Master sends command ID.
+            self.putx([0, ['Command: %s' % cmds[self.cmd]]])
+        elif self.cmdstate in (2, 3, 4):
+            # Bytes 2/3/4: Master sends read address (24bits, MSB-first).
+            self.addr |= (mosi << ((4 - self.cmdstate) * 8))
+            # self.putx([0, ['Read address, byte %d: 0x%02x' % \
+            #                (4 - self.cmdstate, mosi)]])
+            if self.cmdstate == 4:
+                self.putx([0, ['Read address: 0x%06x' % self.addr]])
+                self.addr = 0
+        elif self.cmdstate >= 5:
+            # Bytes 5-x: Master reads data bytes (until CS# de-asserted).
+            # TODO: For now we hardcode 256 bytes per READ command.
+            if self.cmdstate <= 256 + 4: # TODO: While CS# asserted.
+                self.data.append(miso)
+                # self.putx([0, ['New read byte: 0x%02x' % miso]])
+
+            if self.cmdstate == 256 + 4: # TODO: If CS# got de-asserted.
+                # s = ', '.join(map(hex, self.data))
+                s = ''.join(map(chr, self.data))
+                self.putx([0, ['Read data: %s' % s]])
+                self.data = []
+                self.state = IDLE
+                return
+
+        self.cmdstate += 1
+
     def decode(self, ss, es, data):
 
         ptype, mosi, miso = data
@@ -322,6 +375,8 @@ class Decoder(srd.Decoder):
             self.handle_rdsr(mosi, miso)
         elif self.state == CMD_PP:
             self.handle_pp(mosi, miso)
+        elif self.state == CMD_READ:
+            self.handle_read(mosi, miso)
         else:
             self.put(0, 0, self.out_ann, [0, ['Unknown command: 0x%02x' % cmd]])
             self.state = IDLE