Commit graph

1654 commits

Author SHA1 Message Date
George Oikonomou 0e4c02bf3b Update ChipInfo and OSC macros 2016-07-17 00:25:18 +01:00
George Oikonomou f68b77fdfa Remove ROM AUX timer macros
They have been undefined in CCxxwares
2016-07-17 00:25:17 +01:00
George Oikonomou 171fe8d08e Adjust GPIO macros to reflect API in latest CCxxware 2016-07-17 00:25:17 +01:00
George Oikonomou 788cb1e119 Move ROM function macros to separate file 2016-07-17 00:25:17 +01:00
George Oikonomou 568973f6ec Don't flush the CC2538 RF RX FIFO unconditionally
After reading a frame, `read()` checks the status of the RX FIFO:

* If an overflow is detected, the FIFO gets flushed
* If there are more frames in the FIFO, the `cc2538_rf_process` will get polled again in order to read out the next frame.

#1550 changed `read()`, which now performs the above check for non-poll mode, but it then flushes the FIFO unconditionally. Therefore, if there are two or more frames in the FIFO, they will get flushed before the `cc2538_rf_process` has had a chance to read them out. This results in missed frames.

Reproducing this is trivial: Build a CC2538 sniffer and see how it will never show you .15.4 ACK frames. ACK reception completes while `read()` is still streaming the previous captured frame to the host. Upon completion, the FIFO will get flushed and the ACK will get lost.

This pull proposes removing the unconditional flush and reverting to the original logic for non-TSCH operation.

Pinging @thomas-ha here for input regarding poll mode.

This pull sits on top of #1778
2016-07-17 00:24:47 +01:00
Benoît Thébaudeau c05665a16b Merge pull request #1778 from g-oikonomou/contrib/cc2538/rf-driver-code-style
Improve code style of the CC2538 RF driver
2016-07-17 01:22:21 +02:00
George Oikonomou dcad5e7e3f Merge pull request #1727 from g-oikonomou/contrib/cc26xx/trng
Add CC13xx/CC26xx TRNG Support
2016-07-16 23:34:53 +01:00
George Oikonomou 7fdb9849de Remove unnecessary parentheses 2016-07-16 22:35:23 +01:00
Atis Elsts 2fe4b4d5bb CC26xx: enable MCU sleeping while transmitting if and only if not in poll mode 2016-07-16 18:22:20 +01:00
George Oikonomou c359e98bf1 Change mac_timer_init() to static
We also move the function to a different location so we won't have to provide the prototype separately
2016-07-16 17:11:58 +01:00
George Oikonomou 6ef9509dfb Change get_sfd_timestamp() to static
We also move the function to a different location so we won't have to provide the prototype separately
2016-07-16 17:11:57 +01:00
George Oikonomou 833dc89f7c Fix code style 2016-07-16 17:11:57 +01:00
George Oikonomou 0313f9abf1 Merge pull request #1751 from atiselsts/bugfix/cc26xx_etimer_sleep
CC26xx: fix a regression in and refactor LPM code
2016-07-16 14:45:56 +01:00
Antonio Lignan 23a0449a97 Merge pull request #1753 from g-oikonomou/bugfix/cc26xx/missing-include
Add missing include
2016-06-30 22:53:45 +02:00
Atis Elsts b6617f17c5 CC26xx: always request HF crystal oscillator at radio on() 2016-06-29 16:41:33 +03:00
Atis Elsts 9caaf26012 CC26xx: fix a regression in and refactor LPM code 2016-06-29 01:03:06 +03:00
Benoît Thébaudeau 01a533fb75 Merge pull request #1704 from kkrentz/cc2538-aes-fixes
One fix to CC2538 hardware security
2016-06-25 01:30:16 +02:00
Antonio Lignan 6a2d802b9a Merge pull request #1737 from bthebaudeau/cc2538-fix-missing-result-av
cc2538: aes: Fix possibly missing result available status
2016-06-25 00:14:29 +02:00
kkrentz c28b6fb7ba CC2538: Reboot if the crypto engine fails (error handling is too hard) 2016-06-24 01:50:27 -07:00
Benoît Thébaudeau 1da00a482f cc2538: aes: Fix possibly missing result available status
Depending on the use case and on the timings,
aes_auth_crypt_check_status() sometimes never reported an available
result, leading to a deadlock of any protothread waiting for this event,
and to a WDT reset if a protothread was polling it.

This was caused by aes_auth_crypt_start() clearing the result available
interrupt after operations that may rightfully trigger it, leading to a
missed interrupt.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-06-23 22:25:27 +02:00
Benoît Thébaudeau 8a273a248e cc2538: Add configuration for firmware location
Introduce FLASH_CONF_FW_ADDR and FLASH_CONF_FW_SIZE in order to make it
possible to place the firmware anywhere, regardless of Coffee, and
without having to write a custom linker script. Also, handle the default
values properly in order to fix the link breakage reported by
Arthur Fabre <arthur@arthurfabre.com> with COFFEE_CONF_CUSTOM_PORT.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-06-19 23:12:02 +02:00
George Oikonomou de18c16c9f Add CC13xx/CC26xx RNG support to the build 2016-06-15 10:32:03 +01:00
George Oikonomou fd9d878e1d Implement random.h API for the CC13xx/CC26xx 2016-06-15 10:32:03 +01:00
George Oikonomou bb4056903c Add CC13xx/CC26xx TRNG driver 2016-06-15 10:32:03 +01:00
George Oikonomou f8864c67fd Add TRNG CCxxware macros 2016-06-15 10:30:17 +01:00
Atis Elsts e233c3f27f cc26xx: change CCA logic to be standard-compatible; change receiving_packet to return true iff sync (SFD) has been seen 2016-06-14 00:54:33 +03:00
Atis Elsts d85667d535 cc26xx: packet queue changes: allow to read packets after radio has been turned off; make pending_packet() return true when there is a packets being received 2016-06-14 00:54:33 +03:00
Atis Elsts 54e4b5f351 cc26xx: allow IEEE 802.15.4 frames with version 2, required for TSCH 2016-06-14 00:54:33 +03:00
Atis Elsts 80aa30c5da cc26xx: add support for RADIO_PARAM_TX_MODE getting and setting and for LAST_RSSI and LAST_LQI reading 2016-06-14 00:54:33 +03:00
Atis Elsts 25c5f0b744 cc26xx: implement support for CC2650_FAST_RADIO_STARTUP 2016-06-14 00:54:33 +03:00
Atis Elsts 97c1cfc3b4 cc26xx: return the expected value 0 from prepare() in ieee and prop mode radio 2016-06-14 00:54:33 +03:00
Atis Elsts e19fbc996e cc26xx: use CMD_IEEE_MOD_FILT to change address filtering instead of fully restarting the radio 2016-06-14 00:54:33 +03:00
Atis Elsts 3a99639294 cc26xx: implement CC2650_FAST_RADIO_STARTUP option, required for TSCH 2016-06-14 00:54:33 +03:00
Atis Elsts a47fb723e4 cc26xx: enable sync between radio timer and RTC, useful for TSCH 2016-06-14 00:54:33 +03:00
Atis Elsts 95b66657aa cc26xx: add TSCH-related rtimer defines 2016-06-14 00:54:32 +03:00
Atis Elsts ac6f8008fd cc26xx: implement poll mode, hardware timestamps, and other minor changes in the IEEE radio driver 2016-06-14 00:54:32 +03:00
George Oikonomou 678f4344d2 Add missing include 2016-06-13 12:04:47 +01:00
Tiago Koji Castro Shibata c2a0f739f7 Compilation targeting c64
Adds some casts required by cc65 compiler and small fixes
2016-06-12 21:16:01 -03:00
Benoît Thébaudeau b655d92aa4 cc2538: Provide SoC information
Add functions providing the SoC revision, SRAM size, and enabled
hardware features, as well as a function printing SoC information.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-06-11 23:23:38 +02:00
Benoît Thébaudeau b3ea790449 cc2538: sys-ctrl: Provide last reset cause
Add functions providing the last reset cause, one as an integer (ID),
and one as a string.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-06-11 23:23:38 +02:00
Antonio Lignan ee0b02c819 Merge pull request #1684 from g-oikonomou/contrib/cc26xx/aux-ctrl-and-adc
Add CC13xx/CC26xx AUX controller module, ADC support, ALS driver and example
2016-06-07 14:36:28 +02:00
Antonio Lignan b3faefe602 Merge pull request #1433 from mdlemay/x86-mm
X86 memory management
2016-06-05 13:49:49 +02:00
Oliver Schmidt 0151a7c27e Merge pull request #1706 from oliverschmidt/master
Make use of new cl65 option --print-target-path.
2016-06-03 15:13:08 +02:00
Oliver Schmidt ae0c5f0dd0 Make use of new cl65 option --print-target-path.
The new cl65 option --print-target-path allows to get rid of CC65_HOME altogether.
2016-06-03 13:30:25 +02:00
Simon Duquennoy 26bf33c762 Merge pull request #1550 from thomas-ha/tsch-cc2538-port
Port of TSCH for CC2538
2016-06-02 21:33:55 +02:00
Antonio Lignan 6fc4e2535c Merge pull request #1665 from g-oikonomou/contrib/cc26xx-bsl
Consolidate .upload for all CC26xx/CC13xx boards and add login make target
2016-06-01 23:37:29 +02:00
Antonio Lignan 9e1c378919 Merge pull request #1469 from wbober/nrf52dk-pr
Add support for nRF52 DK platform
2016-06-01 23:11:39 +02:00
Antonio Lignan f065971efc Merge pull request #1619 from simonduq/pr/tsch-rtimer16-fix
Fix bug in TSCH for platforms with 16-bit rtimer
2016-06-01 23:03:50 +02:00
Benoît Thébaudeau 09a7566e01 cc2538: coffee: Add default micro-log configuration
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-05-30 23:05:14 +02:00
Benoît Thébaudeau bd961d1cd3 cc2538: Fix possible linker script breakage
The conditional definitions in project-conf.h depending on
CONTIKI_TARGET_<TARGET_NAME> were ignored at link time, which broke the
linker script if it used these definitions, so the flashed applications
could crash or malfunction.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-05-30 23:05:14 +02:00
Atis Elsts 487547d8af Add CC13xx/CC26xx ADC driver 2016-05-29 14:30:07 +01:00
George Oikonomou 43b8bf3d30 Add CCxxware macros for AUX ADC 2016-05-29 14:30:07 +01:00
George Oikonomou 6b40b1b965 Change LPM to power up/down AUX through the AUX controller 2016-05-29 14:30:07 +01:00
George Oikonomou 812f1ada31 Manipulate OSC modules using the AUX controller 2016-05-29 14:28:59 +01:00
George Oikonomou 698ce3a865 Add the AUX controller to the build 2016-05-28 17:37:01 +01:00
George Oikonomou 08dc4b0b21 Add controller for the AUX domain 2016-05-28 17:37:01 +01:00
George Oikonomou 3a34b1f695 Merge pull request #1531 from bkozak-scanimetrics/cc26xx_cc13xx_lpm_fixes
Fixed numerous bugs in CC26xx-CC13xx lpm
2016-05-24 16:45:20 +01:00
Atis Elsts b608b837c2 Add login target to Makefile.cc26xx-cc13xx 2016-05-18 22:10:56 +01:00
George Oikonomou c5bea81bb6 Merge pull request #1530 from herjulf/avr-rss2
Adding AtMegaXXRFR2 support and avr-rss2 platform
2016-05-15 20:38:50 +01:00
Robert Olsson 18876a1fae Adding CRC valid check in rf230bb radios registermaps 2016-05-15 14:15:46 +02:00
George Oikonomou cd5a0ef291 Consolidate .upload for all CC26xx/CC13xx boards
The block that controls the `.upload` target is unnecessarily replicated in multiple sub-board Makefiles. This was originally done because the SmartRF and the Launchpad can be programmed with the c2538-bsl script, whereas the sensortag cannot.

This commit moves the `cc2538-bsl` / `.upload` target logic to the top level cpu Makefile (`cpu/cc26xx-cc13xx/Makefile.cc26xx-cc13xx`). Board makefiles simply set the make variable `BOARD_SUPPORTS_BSL` to 1 to signal that they can be programmed by the BSL script. If `BOARD_SUPPORTS_BSL` is not equal to 1, trying to use the `.upload` target will return an error message.

For example:

```
$ make BOARD=sensortag/cc2650 cc26xx-demo.upload
using saved target 'srf06-cc26xx'
This board cannot be programmed with the ROM bootloader and therefore does not support the .upload target.
```
2016-05-14 19:30:53 +01:00
Jens Dede 7f80b1ad57 Remove include of stdio.h 2016-05-04 11:12:37 +02:00
Jens Dede 59afae85e2 Use if instead of ifdef. Is more contiki standard-compliant 2016-05-02 22:34:58 +02:00
Jens Dede 119291d083 Fix putchar include when using IPv4 2016-05-02 19:13:26 +02:00
Simon Duquennoy bb5e5d5c6b TSCH: use RTIMER_CLOCK_DIFF to compute estimated drift, fixing a bug that would occur on 16-bit rtimer platforms 2016-04-27 14:13:33 +02:00
Michael LeMay 73774def6b x86, galileo: Add sample non-driver protection domain
This patch adds a simple non-driver protection domain sample to serve
as an example for defining other non-driver protection domains.  It
simply performs a ping-pong test of protection domain switching
latency during boot, including optional accesses to a private metadata
region, and prints out the results.
2016-04-22 08:16:43 -07:00
Michael LeMay e0aefd11d9 x86: Add support for SW-switched segment-based protection domains
This patch extends the protection domain framework with a third plugin
that is a hybrid of the previous two.  The hardware task switching
mechanism has a strictly-defined format for TSS data structures that
causes more space to be consumed than would otherwise be required.
This patch defines a smaller data structure that is allocated for each
protection domain, only requiring 32 bytes instead of 128 bytes.  It
uses the same multi-segment memory layout as the TSS-based plugin and
leaves paging disabled.  However, it uses a similar mechanism as the
paging plugin to perform system call dispatches and returns.

For additional information, please refer to cpu/x86/mm/README.md.
2016-04-22 08:16:43 -07:00
Michael LeMay 4cdb7ba9b6 x86: Add TSS-based protection domain support
This patch extends the protection domain framework with an additional
plugin to use Task-State Segment (TSS) structures to offload much of
the work of switching protection domains to the CPU.  This can save
space compared to paging, since paging requires two 4KiB page tables
and one 32-byte page table plus one whole-system TSS and an additional
32-byte data structure for each protection domain, whereas the
approach implemented by this patch just requires a 128-byte data
structure for each protection domain.  Only a small number of
protection domains will typically be used, so
n * 128 < 8328 + (n * 32).

For additional information, please refer to cpu/x86/mm/README.md.

GCC 6 is introducing named address spaces for the FS and GS segments
[1].  LLVM Clang also provides address spaces for the FS and GS
segments [2].  This patch also adds support to the multi-segment X86
memory management subsystem for using these features instead of inline
assembly blocks, which enables type checking to detect some address
space mismatches.

[1] https://gcc.gnu.org/onlinedocs/gcc/Named-Address-Spaces.html
[2] http://llvm.org/releases/3.3/tools/clang/docs/LanguageExtensions.html#target-specific-extensions
2016-04-22 08:16:39 -07:00
George Oikonomou 00d5645d16 Merge pull request #1601 from philrhinehart/bugfix-cc26xx-ble-events
cc26xx-cc13xx BLE beacon event issue
2016-04-18 20:06:33 +01:00
thomas-ha 3a76207b59 Use 64 bit values for MAC timer 2016-04-18 11:40:52 +02:00
Phil Rhinehart 5d5544151f Fixed bug in cc26xx-cc13xx rf-core. When running BLE in conjunction with ContikiMAC, oscillators were modified from an interrupt state causing occasional bus faults and infinite loops. We now check if BLE is active prior to modifiying the oscillators to avoid these conditions. 2016-04-18 17:17:07 +08:00
Phil Rhinehart 2a07dc0e0a This fixes an event handling issue in the cc26xx BLE driver. Currently, the rf_ble_beacon_process triggers the BLE beacon upon receiving any event, rather than verifying that the event timer has expired. This means that any PROCESS_BROADCAST (e.g. any sensor event) will fire the beacon. This commit adds logic to prevent this. 2016-04-18 17:14:37 +08:00
thomas-ha 6262025ef3 code style fixes and insert macros from .h 2016-04-15 15:50:20 +02:00
thomas-ha 3bf05d664e moving macros to .c 2016-04-15 15:50:01 +02:00
thomas-ha 5753fb5173 Clean up the driver
Move mac_timer_init() into set_poll_mode() and remove now unneccesary clear outs and mask outs of interrupt sources and pending interrupts
2016-04-07 15:41:15 +02:00
thomas-ha 9ac859a2af add send_on_cca if query 2016-04-07 15:17:44 +02:00
Oliver Schmidt 2c48f3b232 Added compatibility with W5100 shared access.
If the setup of socket 0 to 3 with 4+2+1+1KB is detected then the W5100 is _not_ initialized, otherwise it does set up socket 0 and 1 with 4KB each. Either way socket 0 is used - now with 4KB instead of 8KB as before.
2016-04-05 21:11:19 +02:00
Oliver Schmidt 4f28289df2 Added a pfs_remove() function and a pfs_seek() stub to the Commodore platforms.
- "Normalized" some Assembly code.
- Implemented CFS_APPEND in pfs_open().
- Made CFS_WRITE work in VICE's virtual disk/file system.
2016-03-28 14:07:35 +02:00
thomas-ha 4e446bc178 fix error 2016-03-23 10:16:06 +01:00
thomas-ha a4f575b8f0 use MAC timer instead of SFD interrupt 2016-03-23 09:08:54 +01:00
thomas-ha fb6e6d9ea3 macros for MAC timer 2016-03-22 18:51:05 +01:00
Michael LeMay 3908253038 x86: Add support for (paging-based) protection domains
This patch implements a simple, lightweight form of protection domains
using a pluggable framework.  Currently, the following plugin is
available:

 - Flat memory model with paging.

The overall goal of a protection domain implementation within this
framework is to define a set of resources that should be accessible to
each protection domain and to prevent that protection domain from
accessing other resources.  The details of each implementation of
protection domains may differ substantially, but they should all be
guided by the principle of least privilege.  However, that idealized
principle is balanced against the practical objectives of limiting the
number of relatively time-consuming context switches and minimizing
changes to existing code.

For additional information, please refer to cpu/x86/mm/README.md.

This patch also causes the C compiler to be used as the default linker
and assembler.
2016-03-21 17:18:06 -07:00
Michael LeMay b0de416682 x86: Adjust UEFI header size
The UEFI GenFw program inserts headers ahead of the code in the UEFI
binary.  The linker script adjusts the starting address of the .text
section to account for that.  This prevents the symbols from being
perturbed.  This patch accounts for a recent change in the size of the
headers added by the GenFw program.
2016-03-21 17:18:06 -07:00
Michael LeMay 93126b57bb x86, galileo: Use IMRs to restrict DMA
This patch configures Isolated Memory Regions (IMRs) to block DMA to
code and data regions that do not contain any data that needs to be
DMA-accessible.
2016-03-17 08:35:49 -07:00
Michael LeMay 58a00b7c23 x86, galileo: Add driver for Isolated Memory Regions (IMRs)
The Intel Quark X1000 SoC includes support for Isolated Memory Regions
(IMRs), which are specified using range registers and associated
control registers that are accessible via the message bus.  This patch
adds a driver for accessing those registers.
2016-03-17 08:35:49 -07:00
Michael LeMay 25c07613c2 x86: Add driver for message bus
The Intel Quark X1000 SoC includes a message bus that is accessible
via PCI configuration registers.  It communicates to various SoC
components such as the Isolated Memory Region (IMR) registers and the
Remote Management Unit.  This patch adds a driver for accessing the
message bus.
2016-03-17 08:35:48 -07:00
thomas-ha 66a0bbcd24 renaming variables back to their original name 2016-03-16 16:38:04 +01:00
Nicolas Tsiftes 9ab327090c Merge pull request #1444 from mdlemay/galileo-always-init-gpio
galileo: Enable I2C and GPIO interrupt sharing and centralize their initialization
2016-03-14 20:09:40 +01:00
thomas-ha 217e623337 remove unused variables 2016-03-10 18:09:00 +01:00
thomas-ha 1b185392e4 make cc2538_sfd_rtime volatile 2016-03-08 16:17:40 +01:00
thomas-ha 73d36ebb6b SFD timestamp
Only save SFD timestamp when we are actually receiving.
2016-03-07 18:34:54 +01:00
Simon Duquennoy dea04c67d7 Change the default IPv6 prefix from aaaa::/64 to fd00::/64 2016-03-07 17:47:44 +01:00
thomas-ha b0a673ca5c Changes to enable TSCH
poll mode for TSCH including SFD timestamps and send_on_cca
2016-03-07 17:46:53 +01:00
thomas-ha b4c2cd9619 Macros for TSCH
US_TO_RTIMERTICKS(US) and RTIMERTICKS_TO_US(T)
2016-03-07 17:25:40 +01:00
Billy Kozak 786aa19cbd Fixed numeruous bus in CC26xx-CC13xx lpm
Bug fixes include:
- keep interrupts disabled during lpm_sleep() so that we don't
  miss any interrupts we may have been expecting
- check that the pending etimer isn't already expired (and don't sleep
  at all if it is)
- check that the about-to-be scheduled rtimer wakeup is neither too
  far into  the future nor too close into the future (or even in the
  past) before actually setting the interrupt (should fix #1509); If
  the time is out of bounds we use a default min or max value instead.
- Correctly handle LPM_MODE_MAX_SUPPORTED set to zero (and added a
  macro for the zero value) so that sleeping can be disabled altogether
- If no etimer is set, we specify a wakeup time which is reasonably far
  into the future instead of setting none at all (this will save on
  power consumption whenever no etimers are set).

Also did a bit of refactoring in that some long functions were broken
into multiple functions.
2016-02-23 10:41:01 -07:00
Robert Olsson d3980668ee Adding support for AtMega128RFR2 and AtMega256RFR2 2016-02-22 20:14:06 +01:00
Michael LeMay 58874ea25d x86, galileo: Refactor I2C and GPIO initialization
This patch revises the I2C and GPIO initialization code to always be
run during platform boot rather than within each process that requires
it.

This patch also revises the gpio-output example to use a pin that is
set as an output by the default pinmux configuration.  Previously, it
used a pin that was set as an output by the pinmux configuration that
is in effect when the OS does not change the pinmux configuration.
2016-02-16 21:19:44 -08:00
Michael LeMay c815fa4511 x86: Use shared ISR for I2C and GPIO
This patch permits interrupts to be generated by both the I2C and GPIO
controllers for simultaneously-executing applications. The controllers
share a single interrupt pin, INTC. Prior to this patch,
quarkX1000_gpio_init() routed INTA to PIRQC and IRQ 10 (due to an
incorrect assumption that INTA is connected to the GPIO controller),
and quarkX1000_i2c_init() routed INTC to PIRQC and IRQ 9. The I2C
controller initialization is a prerequisite for GPIO initialization,
so the final configuration was that INTA and INTC were both routed to
PIRQC and IRQ 10. Thus, only the GPIO ISR was being invoked, even if
the I2C controller was actually responsible for the interrupt.

This patch refactors the I2C and GPIO ISR setup and handler code so
that the shared portions are combined in
cpu/x86/drivers/legacy_pc/shared-isr.[ch].  The I2C and GPIO drivers
communicate their interrupt information to the shared component by
placing structures in a specific section of the binary.
2016-02-16 21:19:44 -08:00
Wojciech Bober 20f9515ed1 nrf52dk: cpu/nrf52832 support 2016-02-15 09:37:38 +01:00
George Oikonomou d42b1b50e5 Allow the caller to access the entire content of CMDSTA
When sending a command to the CC13xx/CC25xx RF core, we wait for command completion by checking the LSB of CMDSTA (correctly so). However, in doing so we also zero out the 3 CMDSTA return bytes. For some commands, those bytes contain useful information (e.g. an RSSI value) and are required by the caller.

This problem manifests itself e.g. in PROP mode `channel_clear()`, whereby the caller will always see an RSSI value of 0.

This pull therefore fixes the logic in `rf_core_send_cmd()` to check for command completion by blocking on the CMDSTA result byte without zeroing out the 3 return bytes.

Fixes #1465
2016-01-24 13:39:14 +00:00