feat: document host provider class

src/content/docs/api/host-provider.md

@@ -1,9 +1,128 @@
 ---
 title: Host Provider
-description: TBD
+description:  The Host Provider instance aggregates data and code available to scripts from the host.
+
 ---
 
-## TBD
+The Host Provider instance aggregates data and code available to scripts from the host.
+
+## Access
+
+The Host Provider instance is a [singleton](https://en.wikipedia.org/wiki/Singleton_pattern) object that is created before hosted scripts are executed.
+
+It may be imported:
+
+```js
+import device from "embedded:provider/builtin"
+```
+
+Or be made available as a [global object](https://developer.mozilla.org/en-US/docs/Glossary/Global_object) named `device`, if the host chooses to do so.
+
+## Instance Properties
+
+### `pin`
+
+An object that maps pin names to [pin specifiers](/glossary/#pin-speficier). More than one pin name may map to the same [pin specifier](/glossary/#pin-speficier).
+
+```js
+console.log(device.pin.led); // logs the value for the on-board LED pin
+console.log(device.pin.button); // logs the value for the on-board button pin
+```
+
+### `i2c`
+
+[IO Bus type](/glossay/#io-bus) for [I<sup>2</sup>C](/api/io-class/i2c) communication
+
+### `serial`
+
+[IO Bus type](/glossay/#io-bus) for [Serial](/api/io-class/serial) communication
+
+### `spi`
+
+[IO Bus type](/glossay/#io-bus) for [SPI](/api/io-class/spi) communication
+
+### `io`
+
+Object of [IO constructors](/api/io-class/) available to the host environment, such as [`Digital`](/api/io-class/digital), [`I2C`](/api/io-class/i2c), and [`SPI`](/api/io-class/spi).
+
+```js
+console.log(device.io.Digital);
+console.log(device.io.I2C);
+console.log(device.io.SPI);
+```
+
+### `provider`
+
+Object of [IO Provider constructors](/api/io-provider-class/) available to the host environment.
+
+### `sensors`
+
+Object of [Sensor constructors](/api/sensor-class/) available to the host environment.
+
+### `displays`
+
+Object of [Display constructors](/api/display-class/) available to the host environment.
+
+### `rtc`
+
+Object of default [Real-time clock constructor options](/api/real-time-clock-class) available to the host environment.
+
+### `network`
+
+Object of networking-related constructor options.
+
+#### `dns.resolver`
+
+Object of default [Domain Name Resolver constructor options](/api/dns-resolver-class).
+
+#### `interface`
+
+Object of default [Network Interface constructor options](/api/network-interface-class).
+
+```js
+console.log(device.network.interface.Ethernet0);
+```
+
+#### `ntp.client`
+
+Object of default [NTP Client constructor options](/api/io-class/ntp-client-class).
+
+#### `http.client`
+
+Object of default [HTTP Client constructor options](/api/io-class/http-client-class).
+
+#### `http.server`
+
+Object of default [HTTP Server constructor options](/api/io-class/http-server-class).
+
+#### `mqtt.client`
+
+Object of default [MQTT Client constructor options](/api/io-class/mqtt-client-class).
+
+#### `mqtts.client`
+
+Object of default secure [MQTT Client constructor options](/api/io-class/mqtt-client-class).
+
+#### `tls.client`
+
+Object of default [TLS Client constructor options](/api/io-class/tls-client-socket).
+
+#### `ws.client`
+
+Object of default [WebSocket Client constructor options](/api/io-class/websocket-client-class).
+
+#### `wss.client`
+
+Object of default secure [WebSocket Client constructor options](/api/io-class/websocket-client-class).
+
+## Examples
+
+The following code is an example of establishing a [SPI](/api/io-class/spi) instance using the properties off the `device` Host Provider:
 
+```js
+let spi = new device.io.SPI(device.spi.default);
+```
 
+## Specifications
 
+[Host Provider instance](https://419.ecma-international.org/#-26-host-provider-instance)

src/content/docs/api/io-class/digital.md

@@ -50,7 +50,9 @@ An input peripheral with the default value as "pulled low", or 0, when nothing e
 
 ### `InputPullUpDown`
 
-### 'Output'
+An input peripheral with the default value as VCC/2, or half of the standard voltage (typically 3.3v).
+
+### `Output`
 
 The IO class accepts the [`write` method](#write) to set the configured pin in push-pull mode: low (0) or high (1).
 

src/content/docs/glossary.md

@@ -41,6 +41,38 @@ Provides the runtime environment for the execution of scripts, as defined by the
 
 [Inter-Integrated Circuit](http://en.wikipedia.org/wiki/I%C2%B2C): a [controller/peripheral](https://learn.sparkfun.com/tutorials/i2c#controller-peripheral) communication protocol that allows one device to control one or more connected devices through two wires, a clock signal (SCL) to keep the components in sync and a data line (SDA).
 
+## IO Bus
+
+Object of two or more pins used to implement a communication protocol such as [Serial](/api/io-class/serial), [SPI](/api/io-class/spi), or [I<sup>2</sup>C](/api/io-class/i2c).
+
+If there is more than one IO bus for a protocol, one may be designated as the `default` bus of that type.
+
+```js
+// example host implementation
+
+const A = {
+    in: 12,
+    out: 13,
+    clock: 14,
+    select: 15,
+    hz: 10_000_000,
+};
+
+const B = {
+    in: 0,
+    out: 1,
+    clock: 2,
+    select: 3,
+    hz: 20_000_000,
+};
+
+device.spi = {
+    A,
+    B,
+    default: B,
+};
+```
+
 ## IP
 
 [Internet Protocol](https://en.wikipedia.org/wiki/Internet_Protocol): the network layer communications protocol for sending data across networks to establish the Internet.