diff --git a/src/cmd.c b/src/cmd.c
index 01204ed..7efaed5 100644
--- a/src/cmd.c
+++ b/src/cmd.c
@@ -204,7 +204,7 @@ void parse_command(const uint8_t *s, uint8_t n)
 	case 'B':
 		if (cmd_flag('@'))
 			pipe.valid = 0;
-		r = pipe.valid;
+		r = pipe.valid | flash_current_block() << 5;
 		if (have_b) {
 			if (bflg && cmd_flag('!') || ~r & bflg) {
 				memcpy(bptr, cmd_buffer, 16);
@@ -228,7 +228,6 @@ void parse_command(const uint8_t *s, uint8_t n)
 			if (~r & bflg)
 				goto error;
 			pipe.valid = r &=~ bflg;
-			r |= pipe.status << 4;
 			goto send_buffer;
 		}
 		break;
@@ -257,7 +256,7 @@ void parse_command(const uint8_t *s, uint8_t n)
 			flash_poll(1);
 		if (cmd_flag('!'))
 			pipe_poll();
-		r = pipe.status;
+		r = pipe.status | flash_current_block();
 		break;
 #ifdef HAVE_FPGA
 	case 'O':
diff --git a/src/dose.py b/src/dose.py
index 2707e61..f5f1c92 100755
--- a/src/dose.py
+++ b/src/dose.py
@@ -169,6 +169,11 @@ class dose_cmd(uart.uart):
             r += dd[4:4+nn]
         return r
 
+    def read_version(self, a="version_str", s=None):
+        r = read_mem(a, s)
+        print(r.decode())
+        return r
+
     _adc_conf = None
     _sigrow = None
 
@@ -564,7 +569,7 @@ class dose_cmd(uart.uart):
     def pipe(self, source=None, dest=None,
              fpga_cmd=4, psize=0, n=0,
              page=0, npages=0,
-             poll=True, stop=False):
+             poll=True, stop=False, parity=None):
         astatus  = flags2int(self.PIPE, dest)
         astatus |= flags2int(self.PIPE, source)
         astatus >>= 8
@@ -599,16 +604,19 @@ class dose_cmd(uart.uart):
         if not npages:
             npages = 1
 
+        if parity == "pipe":
+            status |= 0x30 # PS_BCH
+
         if source & self.PIPE["FLASH"]:
             source = self.PIPE["FLASH"]
             flash |= 4
-            status |= 0x30  # PS_528 | PS_BCH
+            status |= 0x10 # PS_528
             dest &=~ self.PIPE["FLASH"]
             if dest & self.PIPE["FPGA"] and not n:
                 n = 512/64 * npages
         if dest & self.PIPE["FLASH"]:
             flash |= 8
-            status |= 0x30  # PS_528 | PS_BCH
+            status |= 0x10  # PS_528
             if source == self.PIPE["FPGA"] and not n:
                 n = (512*npages + psize - 1) // psize
 
@@ -689,7 +697,7 @@ class dose_cmd(uart.uart):
             f.close()
         return result
 
-    def write_pipe(self, data=[], timeout=2, n=None, parity=False, bfill=b'\0', pfill=b'\xff'):
+    def write_pipe(self, data=[], timeout=2, n=None, parity="pipe", bfill=b'\0', pfill=b'\xff'):
         if isinstance(data, str):
             f = open(data, "rb")
             data = []
@@ -700,6 +708,16 @@ class dose_cmd(uart.uart):
         i = 0
         t = time.time()
         s = 1/256
+
+        # parity="cmd":
+        #   calculate the parity with the 'B%' command
+        # parity="data":
+        #   calculate the parity with python, or take it from array `data[]`
+        # parity="pipe":
+        #   calculate the parity in `pipe_poll()`
+        # !parity:
+        #   Do not care about parity (same as "pipe")
+
         while True:
             if f:
                 page = f.read(512)
@@ -718,13 +736,14 @@ class dose_cmd(uart.uart):
                     page += (64-j)*bfill
                 if pfill:
                     page = (page + 512*pfill)[:512]
-            if len(page)==512 and parity:
+            if len(page)==512 and parity == "data":
                 page += bch.page_parity(page)
             page = [page[j:j+64] for j in range(0,len(page),64)]
             for b in range(8):
                 while True:
                     cc, nn, dd = self.cmd("B")
                     tt = time.time()
+                    bb = nn>>5
                     nn &= 0xf
                     if not nn:
                         t = tt
@@ -740,12 +759,23 @@ class dose_cmd(uart.uart):
                         s = 1
                 if nn:
                     break
-                if parity and b==7:
-                    self.cmd("B@4", page[8])
+                if bb != b:
+                    raise ValueError(f"block number mismatch {b=} != {bb=}")
                 if b >= len(page):
                     break
+                if parity == "data" and b==7:
+                    self.cmd("B4@", page[8])
                 for j in range(4):
-                    self.cmd(f"B{j}", page[b][16*j:16*(j+1)])
+                    B = f"B{j}"
+                    if parity == "cmd":
+                        B += "%"
+                        if not b and not j:
+                            B += "@"
+                        if b==7 and j==3:
+                            B += "!"
+                    ccc,nnn,ddd = self.cmd(B, page[b][16*j:16*(j+1)])
+                    if self._verbose >= 3:
+                        print(f"write_pipe {i=} {b=} {j=} {B=} {nn=}, {ccc=}, {nnn=:#02x}", file=sys.stderr)
                 if self._verbose >= 2:
                     self.peek("pipe", 11)
                 i += 1
@@ -774,6 +804,12 @@ class dose_cmd(uart.uart):
             raise bch.BCHError("galois module not loaded for Parity Error correction")
         return True
 
+    def write_file2flash(self, filename, page, npages=None, parity="pipe"):
+        if npages is None:
+            npages = (os.stat(filename).st_size + 511) // 512
+        self.pipe("CMD", "FLASH", page=page, npages=npages, parity=parity)
+        return self.write_pipe(filename, parity=parity)
+
 def flags2int(FLAGS, flags):
     r = 0
     if flags is None:
diff --git a/src/flash.c b/src/flash.c
index d52ca11..ffa85b6 100644
--- a/src/flash.c
+++ b/src/flash.c
@@ -253,9 +253,11 @@ uint8_t flash_poll(uint8_t rr)
 	if (r & FS_Ready)
 	    goto ready;
 
-	if (r & FS_StBsy && flash_status_bytes[0] & 0x80)
+	if (r & FS_StBsy && flash_status_bytes[0] & 0x80) {
 		// flash is done burning
+		fs.block &= ~7;
 		goto ready;
+	}
 	if (r & FS_Write && fs.block == 9) {
 		// Write or Erase
 		r |= FS_StBsy;
diff --git a/src/pipe.c b/src/pipe.c
index e89cac9..0429f97 100644
--- a/src/pipe.c
+++ b/src/pipe.c
@@ -69,43 +69,43 @@ uint8_t pipe_poll()
 			// flash did not finish yet, successfully
 			goto done;
 
-		// fpga is OUT when the spi is ready.
-		// We are done with this buffer
-
-		r &=~ PS_OUT;
-
 		// Return if next ADC reading is not yet due.
 		// Come back here, until is is.
 
 		if (pipe.source == pipe_adc && !adc_poll(pipe.adc))
 			goto done;
 
+		// fpga is OUT when the spi is ready.
+		// We are done with this buffer
+
+		r &=~ PS_OUT;
+
 		// Continue the flash stream.
-		// PS_BLK is the 64-Bytes buffer number in the page
 
 		valid = 0;
-		if (pipe.source == pipe_flash) {
-			r &= ~ PS_BLK;
-			r |= flash_current_block() & PS_BLK;
+		if (pipe.source == pipe_flash)
 			flash_poll(1);
-		}
 #ifdef HAVE_FPGA
 		// Continue the FPGA stream.
 
-		else if (pipe.source == pipe_fpga) {
-			if (!fpga_start_read())
-				pipe.source = 0;
-		}
+		else if (pipe.source == pipe_fpga && !fpga_start_read())
+			pipe.source = 0;
 #endif
 		goto done;
 	}
 
 	// Waiting for the buffer to fill
 
+	// The current block index in the flash page
+	uint8_t b = flash_current_block();
+	if (pipe.source == pipe_flash)
+		// The valid data is from the previous block
+		b -= 1;
+	b &= 7;
+	uint8_t bflgs = 0x0f;
 	// For 528 bytes pages, the last buffer must be 80 Bytes,
 	// i.e., five cmd_buffers á 16 Bytes
-	uint8_t bflgs = 0x0f;
-	if ((r & PS_5) == PS_5)
+	if (b==7 && r & PS_528)
 		bflgs = 0x1f;
 
 	// Data from the ADC is in named .bss segments. We send
@@ -174,12 +174,12 @@ adc_done:
 	// The buffer shall include BCH Bytes.
 	if (r & PS_BCH) {
 		// First buffer of a page, clear the parity
-		if (!(r & PS_BLK))
+		if (!b)
 			bch4369_init(config.bch_salt);
 		// Add the current buffer to the parity
 		uint8_t *bend = bch4369_stri(flash_buffer, 64);
 		// Last buffer of the page:
-		if (!(~r & PS_BLK)) {
+		if (b==7) {
 			bch4369_fini();
 			// When the Flash is not the source,
 			// and cmd did not provide the parity
@@ -210,8 +210,6 @@ adc_done:
 #endif
 	// Resume the flash stream
 	if (dest & pipe_flash) {
-		r &= ~ PS_BLK;
-		r |= flash_current_block() & PS_BLK;
 		flash_poll(1);
 		if (flash_stream_done())
 			dest &=~ pipe_flash;
diff --git a/src/pipe.h b/src/pipe.h
index 9d9c3f7..11519cf 100644
--- a/src/pipe.h
+++ b/src/pipe.h
@@ -11,8 +11,6 @@ enum pipe_ports {
 	PS_ERR =  0x40,
 	PS_BCH =  0x20,
 	PS_528 =  0x10,
-	PS_BLK =  0x07,
-	PS_5   =  PS_BLK | PS_528, // need 16 bytes more
 
 	AS_CONT = 1,
 	AS_CONFIG = SPI_CONFIG, // = 2