b8de35658f
* Put something on screen * Use the 32bit watch_date_time repr to pass from JS * Implement periodic callbacks * Clear display on enabling * Hook up watch_set_led_color() to SVG (green-only) * Make debug output full-width * Remove default Emscripten canvas * Implement sleep and button clicks * Fix time zone conversion bug in beats-time app * Clean up warnings * Fix pin levels * Set time zone to browser value (if available) * Add basic backup data saving * Silence format specifier warnings in both targets * Remove unnecessary, copied files * Use RTC pointer to clear callbacks (if available) * Use preprocessor define to avoid hardcoding MOVEMENT_NUM_FACES * Change each face to const preprocessor definition * Remove Intl.DateTimeFormat usage * Update shell.html title, header * Add touch start/end event handlers on SVG buttons * Update shell.html * Update folder structure (shared, simulator, hardware under watch-library) * Tease out shared components from watch_slcd * Clean up simulator watch_slcd.c inline JS calls * Fix missing newlines at end of file * Add simulator warnings (except format, unused-paremter) * Implement remaining watch_rtc functions * Fix button bug on mouse down then drag out * Implement remaining watch_slcd functions * Link keyboard events to buttons (for keys A, L, M) * Rewrite event handling (mouse, touch, keyboard) in C * Set explicit text UTF-8 charset in shell.html * Address PR comments * Remove unused directories from include paths
59 lines
1.5 KiB
ReStructuredText
Executable File
59 lines
1.5 KiB
ReStructuredText
Executable File
The USART Synchronous Driver
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============================
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The universal synchronous and asynchronous receiver and transmitter
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(USART) is usually used to transfer data from one device to the other.
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User can set action for flow control pins by function usart_set_flow_control,
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if the flow control is enabled. All the available states are defined in union
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usart_flow_control_state.
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Note that user can set state of flow control pins only if automatic support of
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the flow control is not supported by the hardware.
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Features
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--------
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* Initialization/de-initialization
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* Enabling/disabling
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* Control of the following settings:
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* Baudrate
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* UART or USRT communication mode
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* Character size
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* Data order
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* Flow control
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* Data transfer: transmission, reception
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Applications
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------------
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They are commonly used in a terminal application or low-speed communication
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between devices.
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Dependencies
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------------
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USART capable hardware.
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Concurrency
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-----------
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Write buffer should not be changed while data is being sent.
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Limitations
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-----------
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* The driver does not support 9-bit character size.
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* The "USART with ISO7816" mode can be only used in ISO7816 capable devices.
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And the SCK pin can't be set directly. Application can use a GCLK output PIN
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to generate SCK. For example to communicate with a SMARTCARD with ISO7816
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(F = 372 ; D = 1), and baudrate=9600, the SCK pin output frequency should be
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config as 372*9600=3571200Hz. More information can be refer to ISO7816 Specification.
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Known issues and workarounds
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----------------------------
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N/A
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