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diff --git a/source/errata.rst b/source/errata.rst deleted file mode 100644 index 657abd9..0000000 --- a/source/errata.rst +++ /dev/null @@ -1,140 +0,0 @@ -.. _errata: - -======== - Errata -======== - -This page is a collection of known issues and warnings for each -revision of the Maple board. The failure modes aren't design errors, -but are easy ways to break or damage your board permanently. For a -list of differences between the Maple and Arduinos, see the -:ref:`compatibility reference <compatibility>`. - -The errata are grouped by Maple version ("Rev"). Rev 5 is currently -on sale. If you are unsure which version you own, the :ref:`Maple -hardware page <maple-hardware-identify-rev>` has pictures and -descriptions of each version. - -.. contents:: Contents - :local: - -Maple Rev 5 ------------ - -Known issues: - -* **Pin 3 AIN missing**: Pin 3 is capable of analog input, but the - corresponding "AIN" is missing from its silkscreen. - -* **GPIO 39-43 not configured**: this is really more of a software - "TODO" item. Some of the JTAG header pins are numbered 39-43. These - STM32 pins are indeed fully functional :ref:`GPIO <gpio>` when a - :ref:`JTAG <jtag>` device is not connected, but we have not enabled - them in software and thus they can not be accessed with the regular - :ref:`lang-pinmode` or :ref:`lang-digitalwrite` functions. - -Potential failure modes: - -* **High voltage on non-tolerant pins**: not all header pins are 5V - compatible; so e.g. connecting certain serial devices in the wrong - way could over-voltage the pins. The :ref:`Pin-Mapping Mega Table - <pin-mapping-mega-table>` details which pins are 5V-tolerant. - -Maple Rev 3 ------------ - -Known issues: - -* **Bad/Sticky Buttons**: a number of Rev 3 boards sold in May-June 2010 - have questionable RESET and BUT buttons. - - What seems to have happened is that the flux remover we used to - clean the boards before shipping eroded the plastic internals, which - resulted in intermittent functionality. All buttons on all shipped - boards did function in testing, but some may have been unreliable in - regular use. - - If you have this problem, we will be happy to ship you new buttons - if you think you can re-solder them yourself, or you can ship us - your board and we will swap out that part. - - For reference, the button part number is KMR211GLFS and the flux - remover we used is "Precision Electronics Cleaner" from RadioShack, - which is "Safe on most plastics" and contains Dipropylene glycol - monomethyl ether, hydrotreated heavy naphtha, dipropylene glycol - methyl ether acetate (really?), and carbon dioxide. - -* **Resistors on pins 0 and 1**: these header pins, which are RX/TX on - USART2 (:ref:`Serial2 <lang-serial>`), have resistors in-line - between the STM32 and the headers. These resistors increase the - impedance of the lines for ADC reads and affect the open drain GPIO - functionality of the pins. - - These resistors were accidentally copied over from older Arduino USB - designs, where they appear to protect the USB-Serial converter from - TTL voltage on the headers. - -* **GPIO 39-43 not configured**: this is really more of a software - "TODO" item. Some of the JTAG header pins are numbered 39-43. These - STM32 pins are indeed fully functional :ref:`GPIO <gpio>` when the a - :ref:`JTAG <jtag>` device is not connected, but we have not enabled - them in software and thus they can not be accessed with the regular - :ref:`lang-pinmode` or :ref:`lang-digitalwrite` functions. - -* **Silkscreen Errors**: the silkscreen on the bottom indicated PWM - functionality on pin 25 and listen the external header GND pin as - number 38 (actually 38 is connected to the BUT button). We manually - sharpied over both of these mistakes. - -* **PWM Marketing Mistake**: We originally sold the Maple advertising - 22 channels of 16-bit hardware PWM; actually the Maple only has 15. - -Potential failure modes: - -* **TTL voltage on non-tolerant pins**: not all header pins are 5V - compatible; connecting certain serial devices in the wrong way could - over voltage the pins. The :ref:`Pin-Mapping Mega Table - <pin-mapping-mega-table>` details which pins are 5V-tolerant. - -Maple Rev 1 ------------ - -Known issues: - -* **ADC noise**: generally very high, in particular when the USB port - is being used for communications (including keep-alive pings when - connected to a computer). - - This issue was resolved in Rev 3 with a 4-layer design and a - geometrically isolated ADC V\ :sub:`ref` plane. - -* **Resistors on pins 0 and 1**: these header pins, which are RX/TX on - USART2 (:ref:`Serial2 <lang-serial>`), have resistors in-line - between the STM32 and the headers. These resistors increase the - impedance of the lines for ADC reads and affect the open drain GPIO - functionality of the pins. - - These resistors were accidentally copied over from older Arduino USB - designs, where they appear to protect the USB-Serial converter from - TTL voltage on the headers. - -* **Silkscreen Differences**: the pin numbering scheme on Rev 1 is - different from Rev 3, and thus Rev 3 software is difficult to use - with Rev 1 boards. Notably, the analog input bank is labeled A0-A4 - on Rev 1 but 15-20 on Rev 3, and the extra header bank does not have - a pinout table on the bottom. - -* **No BUT Button**: the BUT button, useful for serial bootloading, - was only added in Rev 3. As a workaround, you can directly short the - appropriate MCU pin to Vcc; see `this forum posting - <http://forums.leaflabs.com/topic.php?id=32#post-126>`_. - -* **PWM Marketing Mistake**: We originally sold the Maple advertising - 22 channels of 16-bit hardware PWM; actually the Maple only has 15. - -Potential failure modes: - -* **TTL voltage on non-tolerant pins**: not all header pins are 5v - compatible; connecting certain serial devices in the wrong way could - over voltage the pins. The :ref:`Pin-Mapping Mega Table - <pin-mapping-mega-table>` details which pins are 5V-tolerant. |