diff --git a/litescope/host/driver/la.py b/litescope/host/driver/la.py
index 5fe0f8b4f..4a9677349 100644
--- a/litescope/host/driver/la.py
+++ b/litescope/host/driver/la.py
@@ -111,8 +111,11 @@ class LiteScopeLADriver():
 	def upload(self):
 		if self.debug:
 			print("uploading")
-		while self.recorder_source_level.read():
-			self.data.append(self.recorder_source_data.read())
+		level = self.recorder_source_level.read()
+		while level:
+			length = self.recorder_source_data.length
+			self.data += self.recorder_source_data.read(repeats=min(128//length, level))
+			level = self.recorder_source_level.read()
 		if self.with_rle:
 			if self.rle_enable.read():
 				self.data = self.data.decode_rle()
diff --git a/litescope/host/driver/reg.py b/litescope/host/driver/reg.py
index 696a94e2a..61390bcc8 100644
--- a/litescope/host/driver/reg.py
+++ b/litescope/host/driver/reg.py
@@ -9,19 +9,24 @@ class MappedReg:
 		self.busword = busword
 		self.mode = mode
 
-	def read(self):
+	def read(self, repeats=None):
 		if self.mode not in ["rw", "ro"]:
 			raise KeyError(name + "register not readable")
-		datas = self.readfn(self.addr, burst_length=self.length)
-		if isinstance(datas, int):
-			return datas
-		else:
+
+		def to_int(v):
+			return 1 if v is None else v
+		read_datas = self.readfn(self.addr, burst_length=self.length, repeats=repeats)
+		datas = []
+		for i in range(to_int(repeats)):
 			data = 0
-			for i in range(self.length):
-				data |= datas[i]
-				if i != (self.length-1):
-					data <<= self.busword
-			return data
+			for j in range(self.length):
+				data = data << self.busword
+				data |= read_datas[i*self.length+j]
+			datas.append(data)
+		if repeats is None:
+			return datas[0]
+		else:
+			return datas
 
 	def write(self, value):
 		if self.mode not in ["rw", "wo"]:
diff --git a/litescope/host/driver/uart.py b/litescope/host/driver/uart.py
index 4bd8f713d..53ab2cac5 100644
--- a/litescope/host/driver/uart.py
+++ b/litescope/host/driver/uart.py
@@ -35,28 +35,27 @@ class LiteScopeUARTDriver:
 		self.uart.flushOutput()
 		self.uart.close()
 
-	def read(self, addr, burst_length=1):
-		self.uart.flushInput()
-		write_b(self.uart, self.cmds["read"])
-		write_b(self.uart, burst_length)
-		addr = addr//4
-		write_b(self.uart, (addr & 0xff000000) >> 24)
-		write_b(self.uart, (addr & 0x00ff0000) >> 16)
-		write_b(self.uart, (addr & 0x0000ff00) >> 8)
-		write_b(self.uart, (addr & 0x000000ff))
-		values = []
-		for i in range(burst_length):
-			val = 0
-			for j in range(4):
-				val = val << 8
-				val |= ord(self.uart.read())
-			if self.debug:
-				print("RD %08X @ %08X" %(val, (addr+i)*4))
-			values.append(val)
-		if burst_length == 1:
-			return values[0]
-		else:
-			return values
+	def read(self, addr, burst_length=None, repeats=None):
+		datas = []
+		def to_int(v):
+			return 1 if v is None else v
+		for i in range(to_int(repeats)):
+			self.uart.flushInput()
+			write_b(self.uart, self.cmds["read"])
+			write_b(self.uart, burst_length)
+			write_b(self.uart, (addr//4 & 0xff000000) >> 24)
+			write_b(self.uart, (addr//4 & 0x00ff0000) >> 16)
+			write_b(self.uart, (addr//4 & 0x0000ff00) >> 8)
+			write_b(self.uart, (addr//4 & 0x000000ff))
+			for j in range(to_int(burst_length)):
+				data = 0
+				for k in range(4):
+					data = data << 8
+					data |= ord(self.uart.read())
+				if self.debug:
+					print("RD %08X @ %08X" %(data, (addr+j)*4))
+				datas.append(data)
+		return datas
 
 	def write(self, addr, data):
 		if isinstance(data, list):
@@ -65,11 +64,10 @@ class LiteScopeUARTDriver:
 			burst_length = 1
 		write_b(self.uart, self.cmds["write"])
 		write_b(self.uart, burst_length)
-		addr = addr//4
-		write_b(self.uart, (addr & 0xff000000) >> 24)
-		write_b(self.uart, (addr & 0x00ff0000) >> 16)
-		write_b(self.uart, (addr & 0x0000ff00) >> 8)
-		write_b(self.uart, (addr & 0x000000ff))
+		write_b(self.uart, (addr//4 & 0xff000000) >> 24)
+		write_b(self.uart, (addr//4 & 0x00ff0000) >> 16)
+		write_b(self.uart, (addr//4 & 0x0000ff00) >> 8)
+		write_b(self.uart, (addr//4 & 0x000000ff))
 		if isinstance(data, list):
 			for i in range(len(data)):
 				dat = data[i]