diff --git a/apps/system/components/DebugConsole/Cargo.toml b/apps/system/components/DebugConsole/Cargo.toml
index b10369e..730158b 100644
--- a/apps/system/components/DebugConsole/Cargo.toml
+++ b/apps/system/components/DebugConsole/Cargo.toml
@@ -7,6 +7,7 @@ members = [
     "kata-logger",
     "kata-shell",
     "kata-uart-client",
+    "zmodem",
 ]
 
 [profile.dev]
diff --git a/apps/system/components/DebugConsole/kata-io/src/lib.rs b/apps/system/components/DebugConsole/kata-io/src/lib.rs
index 5557257..c3519e5 100644
--- a/apps/system/components/DebugConsole/kata-io/src/lib.rs
+++ b/apps/system/components/DebugConsole/kata-io/src/lib.rs
@@ -1,5 +1,8 @@
 #![no_std]
 
+use core::cmp;
+
+#[derive(Debug)]
 pub struct Error;
 
 pub type Result<T> = core::result::Result<T, Error>;
@@ -31,6 +34,8 @@ pub trait Read {
 pub trait Write {
     fn write(&mut self, buf: &[u8]) -> Result<usize>;
 
+    fn flush(&mut self) -> Result<()>;
+
     fn write_all(&mut self, mut buf: &[u8]) -> Result<()> {
         while !buf.is_empty() {
             match self.write(buf) {
@@ -64,3 +69,37 @@ pub enum SeekFrom {
 pub trait Seek {
     fn seek(&mut self, pos: SeekFrom) -> Result<u64>;
 }
+
+impl Read for &[u8] {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        let amt = cmp::min(buf.len(), self.len());
+        let (a, b) = self.split_at(amt);
+        buf[..amt].copy_from_slice(a);
+        *self = b;
+        Ok(amt)
+    }
+}
+
+/// Forwarding implementation of Read for &mut
+impl<'a, T> Read for &'a mut T
+where
+    T: Read,
+{
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        (**self).read(buf)
+    }
+}
+
+/// Forwarding implementation of Write for &mut
+impl<'a, T> Write for &'a mut T
+where
+    T: Write,
+{
+    fn write(&mut self, buf: &[u8]) -> Result<usize> {
+        (**self).write(buf)
+    }
+
+    fn flush(&mut self) -> Result<()> {
+        (**self).flush()
+    }
+}
diff --git a/apps/system/components/DebugConsole/kata-uart-client/src/lib.rs b/apps/system/components/DebugConsole/kata-uart-client/src/lib.rs
index 03136f0..2b1eda8 100644
--- a/apps/system/components/DebugConsole/kata-uart-client/src/lib.rs
+++ b/apps/system/components/DebugConsole/kata-uart-client/src/lib.rs
@@ -40,7 +40,7 @@ pub extern "C" fn logger_log(level: u8, msg: *const cstr_core::c_char) {
 pub struct Rx {}
 
 impl io::Read for Rx {
-    fn read(&mut self, buf: &mut [u8]) -> Result<usize, io::Error> {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         unsafe {
             rx_mutex_lock();
             uart_rx_update(buf.len());
@@ -55,7 +55,7 @@ impl io::Read for Rx {
 pub struct Tx {}
 
 impl io::Write for Tx {
-    fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         unsafe {
             tx_mutex_lock();
             let port = core::slice::from_raw_parts_mut(tx_dataport, buf.len());
@@ -65,4 +65,9 @@ impl io::Write for Tx {
         }
         Ok(buf.len())
     }
+
+    fn flush(&mut self) -> io::Result<()> {
+        // Do nothing. This implementation has no internal buffering.
+        Ok(())
+    }
 }
diff --git a/apps/system/components/DebugConsole/zmodem/Cargo.toml b/apps/system/components/DebugConsole/zmodem/Cargo.toml
index d2261ec..32e7e7c 100644
--- a/apps/system/components/DebugConsole/zmodem/Cargo.toml
+++ b/apps/system/components/DebugConsole/zmodem/Cargo.toml
@@ -5,13 +5,12 @@ license = "MIT OR Apache-2.0"
 version = "0.1.0"
 
 [dependencies]
-clap = "2.21.1"
-crc = "1.4.0"
-env_logger = "0.4.2"
-hex = "0.2.0"
-hexdump = "0.1.0"
-log = "0.3.7"
+crc = { version = "1.4.0", default_features = false }
+hex = { version = "0.4.3", default-features = false, features = ["alloc"] }
+kata-io = { path = "../kata-io" }
+log = { version = "0.4.14", default-features = false }
 
 [dev-dependencies]
-lazy_static = "1"
+env_logger = "0.9.0"
+lazy_static = { version = "1.4.0", features = ["spin"] }
 rand = "0.3.15"
diff --git a/apps/system/components/DebugConsole/zmodem/src/bin/rzm.rs b/apps/system/components/DebugConsole/zmodem/src/bin/rzm.rs
deleted file mode 100644
index fa7d6bd..0000000
--- a/apps/system/components/DebugConsole/zmodem/src/bin/rzm.rs
+++ /dev/null
@@ -1,26 +0,0 @@
-extern crate zmodem;
-
-extern crate clap;
-extern crate env_logger;
-extern crate log;
-
-mod stdinout;
-
-use clap::{App, Arg};
-use std::fs::File;
-use std::path::Path;
-
-fn main() {
-    env_logger::init().unwrap();
-
-    let matches = App::new("Pure Rust implementation of rz utility")
-        .arg(Arg::with_name("file").required(false).index(1))
-        .get_matches();
-
-    let fileopt = matches.value_of("file").unwrap_or("rz-out");
-    let filename = Path::new(fileopt).file_name().unwrap().clone();
-    let file = File::create(filename).expect(&format!("Cannot create file {:?}:", filename));
-
-    let inout = stdinout::CombinedStdInOut::new();
-    zmodem::recv::recv(inout, file).unwrap();
-}
diff --git a/apps/system/components/DebugConsole/zmodem/src/bin/stdinout/mod.rs b/apps/system/components/DebugConsole/zmodem/src/bin/stdinout/mod.rs
deleted file mode 100644
index 9f2a3de..0000000
--- a/apps/system/components/DebugConsole/zmodem/src/bin/stdinout/mod.rs
+++ /dev/null
@@ -1,33 +0,0 @@
-use std::io::*;
-
-pub struct CombinedStdInOut {
-    stdin: Stdin,
-    stdout: Stdout,
-}
-
-impl CombinedStdInOut {
-    pub fn new() -> CombinedStdInOut {
-        CombinedStdInOut {
-            stdin: stdin(),
-            stdout: stdout(),
-        }
-    }
-}
-
-impl Read for CombinedStdInOut {
-    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
-        self.stdin.read(buf)
-    }
-}
-
-impl Write for CombinedStdInOut {
-    fn write(&mut self, buf: &[u8]) -> Result<usize> {
-        let r = self.stdout.write(buf)?;
-        self.stdout.flush()?;
-        Ok(r)
-    }
-
-    fn flush(&mut self) -> Result<()> {
-        self.stdout.flush()
-    }
-}
diff --git a/apps/system/components/DebugConsole/zmodem/src/bin/szm.rs b/apps/system/components/DebugConsole/zmodem/src/bin/szm.rs
deleted file mode 100644
index 3cc7c0c..0000000
--- a/apps/system/components/DebugConsole/zmodem/src/bin/szm.rs
+++ /dev/null
@@ -1,29 +0,0 @@
-extern crate zmodem;
-
-extern crate clap;
-extern crate env_logger;
-extern crate log;
-
-mod stdinout;
-
-use clap::{App, Arg};
-use std::fs::File;
-use std::path::Path;
-
-fn main() {
-    env_logger::init().unwrap();
-
-    let matches = App::new("Pure Rust implementation of sz utility")
-        .arg(Arg::with_name("file").required(true).index(1))
-        .get_matches();
-
-    let fileopt = matches.value_of("file").unwrap();
-    let mut file = File::open(fileopt).unwrap();
-
-    let filename = Path::new(fileopt).file_name().unwrap().clone();
-    let size = file.metadata().map(|x| x.len() as u32).ok();
-
-    let inout = stdinout::CombinedStdInOut::new();
-
-    zmodem::send::send(inout, &mut file, filename.to_str().unwrap(), size).unwrap();
-}
diff --git a/apps/system/components/DebugConsole/zmodem/src/frame.rs b/apps/system/components/DebugConsole/zmodem/src/frame.rs
index 065516e..f8e6829 100644
--- a/apps/system/components/DebugConsole/zmodem/src/frame.rs
+++ b/apps/system/components/DebugConsole/zmodem/src/frame.rs
@@ -1,8 +1,11 @@
+use alloc::string::String;
+use alloc::vec::Vec;
+use core::fmt;
+
 use consts::*;
 use crc;
 use hex::*;
 use proto;
-use std::fmt;
 
 #[derive(Debug, Eq, PartialEq)]
 pub struct Frame {
@@ -59,7 +62,7 @@ impl Frame {
         out.append(&mut crc);
 
         if self.header == ZHEX {
-            let hex = out.drain(4..).collect::<Vec<u8>>().to_hex();
+            let hex = out.drain(4..).collect::<Vec<u8>>().encode_hex::<String>();
             out.extend_from_slice(&hex.as_bytes());
         }
 
@@ -95,8 +98,8 @@ fn get_crc(header: u8, buf: &[u8]) -> Vec<u8> {
     };
 
     match header {
-        ZBIN32 => crc::get_crc32(&buf[offset..], None).to_vec(),
-        _ => crc::get_crc16(&buf[offset..], None).to_vec(),
+        ZBIN32 => crc::get_crc32(&buf[offset..], None).into(),
+        _ => crc::get_crc16(&buf[offset..], None).into(),
     }
 }
 
@@ -139,6 +142,8 @@ impl fmt::Display for Frame {
 
 #[test]
 fn test_frame() {
+    use alloc::vec;
+
     assert_eq!(
         Frame::new(ZBIN, 0).build(),
         vec![ZPAD, ZLDE, ZBIN, 0, 0, 0, 0, 0, 0, 0]
diff --git a/apps/system/components/DebugConsole/zmodem/src/lib.rs b/apps/system/components/DebugConsole/zmodem/src/lib.rs
index 90a07f4..7458e85 100644
--- a/apps/system/components/DebugConsole/zmodem/src/lib.rs
+++ b/apps/system/components/DebugConsole/zmodem/src/lib.rs
@@ -1,15 +1,16 @@
-#[macro_use]
-extern crate log;
+#![no_std]
 
+extern crate alloc;
 extern crate crc as crc32;
 extern crate hex;
-extern crate hexdump;
+extern crate kata_io;
+#[macro_use]
+extern crate log;
 
 mod consts;
 mod crc;
 mod frame;
 mod proto;
-mod rwlog;
 
 pub mod recv;
 pub mod send;
diff --git a/apps/system/components/DebugConsole/zmodem/src/proto.rs b/apps/system/components/DebugConsole/zmodem/src/proto.rs
index 585a5da..7dc8ed0 100644
--- a/apps/system/components/DebugConsole/zmodem/src/proto.rs
+++ b/apps/system/components/DebugConsole/zmodem/src/proto.rs
@@ -1,6 +1,8 @@
-use hex::*;
-use log::LogLevel::Debug;
-use std::io;
+use alloc::vec::Vec;
+use alloc::{format, vec};
+
+use kata_io as io;
+use log::Level::Debug;
 
 use consts::*;
 use crc::*;
@@ -55,7 +57,7 @@ where
     read_exact_unescaped(r, &mut v)?;
 
     if header == ZHEX {
-        v = match FromHex::from_hex(&v) {
+        v = match hex::decode(&v) {
             Ok(x) => x,
             _ => {
                 error!("from_hex error");
@@ -104,15 +106,37 @@ where
     Ok(())
 }
 
+/// Read into buf until and including the byte delim
+///
+/// This is a one-off implementation of a method of io::BufRead that the
+/// original lexxvir/zmodem had used. (So far kata_io is deferring implementing
+/// buffering to validate it will become needed in more places.)
+fn read_until<R>(r: &mut R, delim: u8, buf: &mut Vec<u8>) -> io::Result<usize>
+where
+    R: io::Read,
+{
+    let mut n = 0usize;
+    loop {
+        let b = read_byte(r)?;
+        buf.push(b);
+        n += 1;
+        if b == delim {
+            break;
+        }
+    }
+
+    Ok(n)
+}
+
 /// Receives sequence: <escaped data> ZLDE ZCRC* <CRC bytes>
 /// Unescapes sequencies such as 'ZLDE <escaped byte>'
 /// If Ok returns <unescaped data> in buf and ZCRC* byte as return value
 pub fn recv_zlde_frame<R>(header: u8, r: &mut R, buf: &mut Vec<u8>) -> io::Result<Option<u8>>
 where
-    R: io::BufRead,
+    R: io::Read,
 {
     loop {
-        r.read_until(ZLDE, buf)?;
+        read_until(r, ZLDE, buf)?;
         let b = read_byte(r)?;
 
         if !is_escaped(b) {
@@ -148,7 +172,7 @@ pub fn recv_data<RW, OUT>(
     out: &mut OUT,
 ) -> io::Result<bool>
 where
-    RW: io::Write + io::BufRead,
+    RW: io::Write + io::Read,
     OUT: io::Write,
 {
     let mut buf = Vec::new();
@@ -182,7 +206,8 @@ where
                 debug!("CCRCG: CRC next, frame continues nonstop");
             }
             _ => {
-                panic!(format!("unexpected ZCRC byte: {:02X}", zcrc));
+                error!("unexpected ZCRC byte: {:02X}", zcrc);
+                return Err(io::Error);
             }
         }
     }
diff --git a/apps/system/components/DebugConsole/zmodem/src/recv.rs b/apps/system/components/DebugConsole/zmodem/src/recv.rs
index 07ed55b..2b69531 100644
--- a/apps/system/components/DebugConsole/zmodem/src/recv.rs
+++ b/apps/system/components/DebugConsole/zmodem/src/recv.rs
@@ -1,11 +1,11 @@
-use std::io::{Read, Result, Write};
-use std::str::from_utf8;
-use std::{thread, time};
+use alloc::vec::Vec;
+use core::str::from_utf8;
+
+use kata_io as io;
 
 use consts::*;
 use frame::*;
 use proto::*;
-use rwlog;
 
 #[derive(Debug, PartialEq)]
 enum State {
@@ -53,12 +53,13 @@ impl State {
 }
 
 /// Receives data by Z-Modem protocol
-pub fn recv<RW, W>(rw: RW, mut w: W) -> Result<usize>
+pub fn recv<RW, W>(rw: RW, mut w: W) -> io::Result<usize>
 where
-    RW: Read + Write,
-    W: Write,
+    RW: io::Read + io::Write,
+    W: io::Write,
 {
-    let mut rw_log = rwlog::ReadWriteLog::new(rw);
+    let mut rw_log = rw;
+
     let mut count = 0;
 
     let mut state = State::new();
@@ -121,7 +122,11 @@ where
             }
             State::Done => {
                 write_zfin(&mut rw_log)?;
-                thread::sleep(time::Duration::from_millis(10)); // sleep a bit
+                // NB: lexxvir/zmodem had a 10ms sleep here that has been removed
+                // due to no_std. Here we change it to flush() so that a return
+                // from this function does really indicate all the bytes have
+                // been written.
+                rw_log.flush()?;
             }
         }
     }
@@ -129,9 +134,9 @@ where
     Ok(count as usize)
 }
 
-fn recv_error<W>(w: &mut W, state: &State, count: u32) -> Result<()>
+fn recv_error<W>(w: &mut W, state: &State, count: u32) -> io::Result<()>
 where
-    W: Write,
+    W: io::Write,
 {
     // TODO: flush input
 
diff --git a/apps/system/components/DebugConsole/zmodem/src/send.rs b/apps/system/components/DebugConsole/zmodem/src/send.rs
index 639b9ab..2395d01 100644
--- a/apps/system/components/DebugConsole/zmodem/src/send.rs
+++ b/apps/system/components/DebugConsole/zmodem/src/send.rs
@@ -1,9 +1,8 @@
-use std::io::{Read, Result, Seek, SeekFrom, Write};
+use kata_io as io;
 
 use consts::*;
 use frame::*;
 use proto::*;
-use rwlog;
 
 const SUBPACKET_SIZE: usize = 1024 * 8;
 const SUBPACKET_PER_ACK: usize = 10;
@@ -63,12 +62,12 @@ impl State {
     }
 }
 
-pub fn send<RW, R>(rw: RW, r: &mut R, filename: &str, filesize: Option<u32>) -> Result<()>
+pub fn send<RW, R>(rw: RW, r: &mut R, filename: &str, filesize: Option<u32>) -> io::Result<()>
 where
-    RW: Read + Write,
-    R: Read + Seek,
+    RW: io::Read + io::Write,
+    R: io::Read + io::Seek,
 {
-    let mut rw_log = rwlog::ReadWriteLog::new(rw);
+    let mut rw_log = rw;
 
     let mut data = [0; SUBPACKET_SIZE];
     let mut offset: u32;
@@ -105,7 +104,7 @@ where
             }
             State::SendingData => {
                 offset = frame.get_count();
-                r.seek(SeekFrom::Start(offset as u64))?;
+                r.seek(io::SeekFrom::Start(offset as u64))?;
 
                 let num = r.read(&mut data)?;
 
diff --git a/apps/system/components/DebugConsole/zmodem/tests/lib.rs b/apps/system/components/DebugConsole/zmodem/tests/lib.rs
index e12ee50..cc55497 100644
--- a/apps/system/components/DebugConsole/zmodem/tests/lib.rs
+++ b/apps/system/components/DebugConsole/zmodem/tests/lib.rs
@@ -12,6 +12,12 @@ use std::result;
 use std::thread::{sleep, spawn};
 use std::time::*;
 
+extern crate kata_io;
+
+fn forget_err(_e: std::io::Error) -> kata_io::Error {
+    kata_io::Error {}
+}
+
 struct InOut<R: Read, W: Write> {
     r: R,
     w: W,
@@ -23,24 +29,66 @@ impl<R: Read, W: Write> InOut<R, W> {
     }
 }
 
-impl<R: Read, W: Write> Read for InOut<R, W> {
-    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
-        self.r.read(buf)
+impl<R: Read, W: Write> kata_io::Read for InOut<R, W> {
+    fn read(&mut self, buf: &mut [u8]) -> kata_io::Result<usize> {
+        self.r.read(buf).map_err(forget_err)
     }
 }
 
-impl<R: Read, W: Write> Write for InOut<R, W> {
-    fn write(&mut self, buf: &[u8]) -> Result<usize> {
-        self.w.write(buf)
+impl<R: Read, W: Write> kata_io::Write for InOut<R, W> {
+    fn write(&mut self, buf: &[u8]) -> kata_io::Result<usize> {
+        self.w.write(buf).map_err(forget_err)
     }
 
-    fn flush(&mut self) -> Result<()> {
-        self.w.flush()
+    fn flush(&mut self) -> kata_io::Result<()> {
+        self.w.flush().map_err(forget_err)
+    }
+}
+
+/// Minimal vector-backed kata_io::Read and kata_io::Write
+///
+/// This is a workaround to not being able to implement the kata_io traits for
+/// std::io::Cursor in this file, since none of those come from the current
+/// crate.
+struct WrappedCursor<T> {
+    c: std::io::Cursor<T>,
+}
+
+impl<T> WrappedCursor<T> {
+    pub fn into_inner(self) -> T {
+        self.c.into_inner()
+    }
+}
+
+impl kata_io::Read for WrappedCursor<&Vec<u8>> {
+    fn read(&mut self, buf: &mut [u8]) -> kata_io::Result<usize> {
+        self.c.read(buf).map_err(forget_err)
+    }
+}
+
+impl kata_io::Write for WrappedCursor<Vec<u8>> {
+    fn write(&mut self, buf: &[u8]) -> kata_io::Result<usize> {
+        self.c.write(buf).map_err(forget_err)
+    }
+
+    fn flush(&mut self) -> kata_io::Result<()> {
+        self.c.flush().map_err(forget_err)
+    }
+}
+
+impl kata_io::Seek for WrappedCursor<&Vec<u8>> {
+    fn seek(&mut self, pos: kata_io::SeekFrom) -> kata_io::Result<u64> {
+        let std_pos = match pos {
+            kata_io::SeekFrom::Start(n) => std::io::SeekFrom::Start(n),
+            kata_io::SeekFrom::End(n) => std::io::SeekFrom::End(n),
+            kata_io::SeekFrom::Current(n) => std::io::SeekFrom::Current(n),
+        };
+        self.c.seek(std_pos).map_err(forget_err)
     }
 }
 
 lazy_static! {
-    static ref LOG_INIT: result::Result<(), log::SetLoggerError> = env_logger::init();
+    static ref LOG_INIT: result::Result<(), log::SetLoggerError> = Ok(env_logger::init());
     static ref RND_VALUES: Vec<u8> = {
         use rand::Rng;
         let mut rng = rand::thread_rng();
@@ -69,7 +117,9 @@ fn recv_from_sz() {
     let child_stdout = sz.stdout.unwrap();
     let mut inout = InOut::new(child_stdout, child_stdin);
 
-    let mut c = Cursor::new(Vec::new());
+    let mut c = WrappedCursor {
+        c: Cursor::new(Vec::new()),
+    };
     zmodem::recv::recv(&mut inout, &mut c).unwrap();
 
     sleep(Duration::from_millis(300));
@@ -97,7 +147,9 @@ fn send_to_rz() {
 
     let len = RND_VALUES.len() as u32;
     let copy = RND_VALUES.clone();
-    let mut cur = Cursor::new(&copy);
+    let mut cur = WrappedCursor {
+        c: Cursor::new(&copy),
+    };
 
     sleep(Duration::from_millis(300));
 
@@ -141,12 +193,16 @@ fn lib_send_recv() {
         let mut inout = InOut::new(inf, outf);
 
         let origin = RND_VALUES.clone();
-        let mut c = Cursor::new(&origin);
+        let mut c = WrappedCursor {
+            c: Cursor::new(&origin),
+        };
 
         zmodem::send::send(&mut inout, &mut c, "test", None).unwrap();
     });
 
-    let mut c = Cursor::new(Vec::new());
+    let mut c = WrappedCursor {
+        c: Cursor::new(Vec::new()),
+    };
 
     let inf = File::open("test-fifo1").unwrap();
     let outf = OpenOptions::new().write(true).open("test-fifo2").unwrap();