diff --git a/src/App.svelte b/src/App.svelte
index b94e72c..1d3f108 100644
--- a/src/App.svelte
+++ b/src/App.svelte
@@ -12,7 +12,7 @@
 <ModeWatcher />
 <Toaster position="bottom-center" duration={2000} />
 
-<div class="max-w-screen-xl min-h-screen m-auto p-8 stack gap-4">
+<div class="max-w-screen-xl min-h-dvh m-auto p-8 stack gap-4">
   {#if unsupported}
     <Unsupported />
   {:else}
diff --git a/src/lib/components/ImplicitNumericInput.svelte b/src/lib/components/ImplicitNumericInput.svelte
new file mode 100644
index 0000000..552b99b
--- /dev/null
+++ b/src/lib/components/ImplicitNumericInput.svelte
@@ -0,0 +1,43 @@
+<script lang="ts">
+  import { cn, showNumber } from '$lib/utils'
+  import type { HTMLAttributes } from 'svelte/elements'
+
+  interface Props extends Omit<HTMLAttributes<HTMLInputElement>, 'type' | 'inputmode' | 'onchange' | 'value'> {
+    min: number
+    max: number
+    value: number
+    onchange: (value: number) => void
+  }
+
+  const { min, max, value, onchange, class: classNames, ...restProps }: Props = $props()
+
+  const size = $derived(Math.max(String(min).length, String(max).length))
+</script>
+
+<input
+  type="text"
+  inputmode="numeric"
+  class={cn(
+    'bg-muted rounded-md focus-visible:outline-none focus-visible:ring-ring focus-visible:ring-1 focus-visible:ring-offset-2 px-1 mx-0.5',
+    classNames,
+  )}
+  {size}
+  maxlength={size}
+  style:field-sizing="content"
+  value={showNumber(value)}
+  onchange={e => {
+    let n = Number(e.currentTarget.value)
+
+    if (isNaN(n)) {
+      e.currentTarget.value = showNumber(value)
+      return
+    }
+
+    if (n < min) n = min
+    if (n > max) n = max
+
+    e.currentTarget.value = showNumber(n)
+    onchange(n)
+  }}
+  {...restProps}
+/>
diff --git a/src/lib/components/MoreInfo.svelte b/src/lib/components/MoreInfo.svelte
index 888b3a8..280ebd7 100644
--- a/src/lib/components/MoreInfo.svelte
+++ b/src/lib/components/MoreInfo.svelte
@@ -1,15 +1,22 @@
 <script lang="ts">
-  import IconInfo from '~icons/material-symbols/info'
+  import type { PopoverTriggerProps } from 'bits-ui'
 
+  import IconInfo from '~icons/material-symbols/info'
   import * as Popover from '$lib/components/ui/popover'
+
+  interface Props extends PopoverTriggerProps {}
+
+  const { children, ...restProps }: Props = $props()
 </script>
 
 <Popover.Root>
-  <Popover.Trigger aria-label="More info">
+  <Popover.Trigger aria-label="More info" {...restProps}>
     <IconInfo class="text-muted-foreground text-sm" aria-hidden />
   </Popover.Trigger>
 
   <Popover.Content class="text-sm">
-    <slot />
+    {#if children}
+      {@render children()}
+    {/if}
   </Popover.Content>
 </Popover.Root>
diff --git a/src/lib/constants.ts b/src/lib/constants.ts
new file mode 100644
index 0000000..8d4d8b2
--- /dev/null
+++ b/src/lib/constants.ts
@@ -0,0 +1,10 @@
+export const INKCLIP_VID = 0x1209
+export const INKCLIP_PID = 0xc9c9
+
+export const INKCLIP_WIDTH = 200 // px
+export const INKCLIP_HEIGHT = 200 // px
+
+export const INKCLIP_ASPECT_RATIO = INKCLIP_WIDTH / INKCLIP_HEIGHT
+export const BYTES_IN_A_ROW = INKCLIP_WIDTH / 8
+
+export const WRITE_TIME = 2000 // ms
diff --git a/src/lib/contexts/device.svelte.ts b/src/lib/contexts/device.svelte.ts
index c6ec1be..0241c1c 100644
--- a/src/lib/contexts/device.svelte.ts
+++ b/src/lib/contexts/device.svelte.ts
@@ -1,8 +1,9 @@
+import { INKCLIP_PID, INKCLIP_VID } from '$lib/constants'
 import { getContext, setContext } from 'svelte'
 import { toast } from 'svelte-sonner'
 
 function isInkclip(dev: HIDDevice) {
-  return dev.vendorId == 0xc0de && dev.productId == 0xcafe
+  return dev.vendorId == INKCLIP_VID && dev.productId == INKCLIP_PID
 }
 
 export interface DeviceContext {
diff --git a/src/lib/contexts/rendered.svelte.ts b/src/lib/contexts/rendered.svelte.ts
index 2a18110..34fc423 100644
--- a/src/lib/contexts/rendered.svelte.ts
+++ b/src/lib/contexts/rendered.svelte.ts
@@ -4,6 +4,7 @@ import { withTransform } from '$lib/image/transform'
 import type { ConversionConfig } from './config.svelte'
 import { Scaler } from '$lib/image/scaler'
 import { Quantizer } from '$lib/image/quantizer'
+import { INKCLIP_HEIGHT, INKCLIP_WIDTH } from '$lib/constants'
 
 export interface RenderedContext {
   rendered: number[] | null
@@ -15,7 +16,7 @@ export function getRenderedContext(): Readonly<RenderedContext> {
   return getContext(RenderedContextToken)
 }
 
-const scaler = new Scaler(200, 200)
+const scaler = new Scaler(INKCLIP_WIDTH, INKCLIP_HEIGHT)
 
 export function createRenderedContext(
   imageCtx: Readonly<ImageContext>,
@@ -33,7 +34,7 @@ export function createRenderedContext(
     })
   )
 
-  const canvas = new OffscreenCanvas(200, 200)
+  const canvas = new OffscreenCanvas(INKCLIP_WIDTH, INKCLIP_HEIGHT)
   const canvasCtx = canvas.getContext('2d', {
     willReadFrequently: true,
   })!
@@ -49,7 +50,7 @@ export function createRenderedContext(
     withTransform(canvasCtx, config.transform, () => {
       const bg = config.backgroundColor
       canvasCtx.fillStyle = `rgb(${bg} ${bg} ${bg})`
-      canvasCtx.fillRect(0, 0, 200, 200)
+      canvasCtx.fillRect(0, 0, INKCLIP_WIDTH, INKCLIP_HEIGHT)
       const { dx, dy, dWidth, dHeight } = scaler.scale(config.scaleMode, bitmap)
       canvasCtx.drawImage(bitmap, dx, dy, dWidth, dHeight)
     })
diff --git a/src/lib/image/transform.ts b/src/lib/image/transform.ts
index 1988c13..20c25b9 100644
--- a/src/lib/image/transform.ts
+++ b/src/lib/image/transform.ts
@@ -1,3 +1,5 @@
+import { INKCLIP_HEIGHT, INKCLIP_WIDTH } from '$lib/constants'
+
 export type Rotation = 0 | 90 | 180 | 270
 export type Side = 'obverse' | 'reverse'
 export type Operation = 'cw' | 'ccw' | 'h' | 'v'
@@ -52,15 +54,18 @@ function withCtx<T>(ctx: Context2D, pre: () => void, action: () => T): T {
 }
 
 export function withTransform<T>(ctx: Context2D, transform: Transform, action: () => T): T {
+  const centerX = INKCLIP_WIDTH / 2
+  const centerY = INKCLIP_HEIGHT / 2
+
   return withCtx(
     ctx,
     () => {
-      ctx.translate(100, 100)
+      ctx.translate(centerX, centerY)
       if (transform.side === 'reverse') {
         ctx.scale(-1, 1)
       }
       ctx.rotate((transform.rotation / 180) * Math.PI)
-      ctx.translate(-100, -100)
+      ctx.translate(-centerX, -centerY)
     },
     action
   )
diff --git a/src/lib/layouts/connect/ConnectButton.svelte b/src/lib/layouts/connect/ConnectButton.svelte
index b17160f..4cad155 100644
--- a/src/lib/layouts/connect/ConnectButton.svelte
+++ b/src/lib/layouts/connect/ConnectButton.svelte
@@ -1,6 +1,7 @@
 <script lang="ts">
   import { Button } from '$lib/components/ui/button'
 
+  import { INKCLIP_PID, INKCLIP_VID } from '$lib/constants'
   import { getDeviceContext } from '$lib/contexts/device.svelte'
 
   const deviceCtx = getDeviceContext()
@@ -9,8 +10,8 @@
     const devs = await navigator.hid.requestDevice({
       filters: [
         {
-          vendorId: 0xc0de,
-          productId: 0xcafe,
+          vendorId: INKCLIP_VID,
+          productId: INKCLIP_PID,
         },
       ],
     })
diff --git a/src/lib/layouts/edit/controls/BackgroundColorSlider.svelte b/src/lib/layouts/edit/controls/BackgroundColorSlider.svelte
index b672191..7933cd3 100644
--- a/src/lib/layouts/edit/controls/BackgroundColorSlider.svelte
+++ b/src/lib/layouts/edit/controls/BackgroundColorSlider.svelte
@@ -2,6 +2,7 @@
   import { Label } from '$lib/components/ui/label'
   import { Slider } from '$lib/components/ui/slider'
   import MoreInfo from '$lib/components/MoreInfo.svelte'
+  import ImplicitNumericInput from '$lib/components/ImplicitNumericInput.svelte'
 
   import { getConversionConfig } from '$lib/contexts/config.svelte'
 
@@ -10,10 +11,18 @@
   let value = $derived(config.backgroundColor)
 </script>
 
-<div class="stack gap-4" role="group" aria-label="Background color">
+<div class="stack gap-4" role="group" aria-labelledby="background-color-input-label">
   <div class="row gap-1 text-sm">
     <Label id="background-color-input-label">Background Color</Label>
-    <span class="font-normal text-muted-foreground"> = {value} </span>
+    <span class="font-normal text-muted-foreground">
+      =<ImplicitNumericInput
+        min={0}
+        max={0xff}
+        {value}
+        onchange={v => (config.bias = value = v)}
+        aria-labelledby="background-color-input-label"
+      />
+    </span>
     <MoreInfo>The color used for transparent pixels.</MoreInfo>
   </div>
 
@@ -22,7 +31,7 @@
     bind:value
     onValueCommit={() => (config.backgroundColor = value)}
     min={0}
-    max={255}
+    max={0xff}
     step={1}
     aria-labelledby="background-color-input-label"
   />
diff --git a/src/lib/layouts/edit/controls/ControlsSection.svelte b/src/lib/layouts/edit/controls/ControlsSection.svelte
index 42fb039..bba1110 100644
--- a/src/lib/layouts/edit/controls/ControlsSection.svelte
+++ b/src/lib/layouts/edit/controls/ControlsSection.svelte
@@ -1,5 +1,4 @@
 <script lang="ts">
-  import { DEFAULT_DITHERING_KERNEL } from '$lib/image/quantizer'
   import { Transform } from '$lib/image/transform'
 
   import { Button } from '$lib/components/ui/button'
@@ -15,6 +14,8 @@
 
   import { getConversionConfig } from '$lib/contexts/config.svelte'
   import { getImageContext } from '$lib/contexts/image.svelte'
+  import { INKCLIP_HEIGHT, INKCLIP_WIDTH } from '$lib/constants'
+  import { DEFAULT_DITHERING_KERNEL } from '$lib/image/quantizer'
 
   const imageCtx = getImageContext()
   const config = getConversionConfig()
@@ -23,13 +24,13 @@
 
   function imageNonSquare() {
     if (imageCtx.image === null) return false
-    return imageCtx.image.height !== imageCtx.image.width
+    return imageCtx.image.height * INKCLIP_WIDTH !== imageCtx.image.width * INKCLIP_HEIGHT
   }
 
   function restoreDefaultImageSettings() {
     config.scaleMode = 'fit'
     config.transform = new Transform()
-    config.backgroundColor = 255
+    config.backgroundColor = 0xff
     config.ditheringKernel = DEFAULT_DITHERING_KERNEL
     config.contrast = 0
     config.bias = 0
diff --git a/src/lib/layouts/edit/controls/conversion/BiasSlider.svelte b/src/lib/layouts/edit/controls/conversion/BiasSlider.svelte
index 7fbb1d1..f7f141d 100644
--- a/src/lib/layouts/edit/controls/conversion/BiasSlider.svelte
+++ b/src/lib/layouts/edit/controls/conversion/BiasSlider.svelte
@@ -2,6 +2,7 @@
   import { Label } from '$lib/components/ui/label'
   import { Slider } from '$lib/components/ui/slider'
   import MoreInfo from '$lib/components/MoreInfo.svelte'
+  import ImplicitNumericInput from '$lib/components/ImplicitNumericInput.svelte'
 
   import { getConversionConfig } from '$lib/contexts/config.svelte'
 
@@ -10,10 +11,18 @@
   let value = $derived(Math.round(config.bias * 100))
 </script>
 
-<div class="stack gap-4" role="group" aria-label="Bias">
+<div class="stack gap-4" role="group" aria-labelledby="bias-input-label">
   <div class="row gap-1 text-sm">
     <Label id="bias-input-label">Bias</Label>
-    <span class="font-normal text-muted-foreground"> = {value}% </span>
+    <span class="font-normal text-muted-foreground">
+      =<ImplicitNumericInput
+        min={-100}
+        max={100}
+        {value}
+        onchange={v => (config.bias = (value = v) / 100)}
+        aria-labelledby="bias-input-label"
+      />%
+    </span>
     <MoreInfo>
       Whether the conversion algorithm should bias the entire image towards white (negative) or black (positive).
     </MoreInfo>
diff --git a/src/lib/layouts/edit/controls/conversion/ContrastSlider.svelte b/src/lib/layouts/edit/controls/conversion/ContrastSlider.svelte
index 2b290ec..ca131e5 100644
--- a/src/lib/layouts/edit/controls/conversion/ContrastSlider.svelte
+++ b/src/lib/layouts/edit/controls/conversion/ContrastSlider.svelte
@@ -2,6 +2,7 @@
   import { Label } from '$lib/components/ui/label'
   import { Slider } from '$lib/components/ui/slider'
   import MoreInfo from '$lib/components/MoreInfo.svelte'
+  import ImplicitNumericInput from '$lib/components/ImplicitNumericInput.svelte'
 
   import { getConversionConfig } from '$lib/contexts/config.svelte'
 
@@ -10,10 +11,18 @@
   let value = $derived(Math.round(config.contrast * 100))
 </script>
 
-<div class="stack gap-4" role="group" aria-label="Contrast">
+<div class="stack gap-4" role="group" aria-labelledby="contrast-input-label">
   <div class="row gap-1 text-sm">
     <Label id="contrast-input-label">Contrast</Label>
-    <span class="font-normal text-muted-foreground"> = {value}% </span>
+    <span class="font-normal text-muted-foreground">
+      =<ImplicitNumericInput
+        min={0}
+        max={100}
+        {value}
+        onchange={v => (config.contrast = (value = v) / 100)}
+        aria-labelledby="contrast-input-label"
+      />%
+    </span>
     <MoreInfo>
       How eager the conversion algorithm should push colors towards the two ends (black and white) of the grayscale.
     </MoreInfo>
diff --git a/src/lib/layouts/edit/controls/conversion/dither/DitherSwitch.svelte b/src/lib/layouts/edit/controls/conversion/dither/DitherSwitch.svelte
index 8fc9ea9..958a925 100644
--- a/src/lib/layouts/edit/controls/conversion/dither/DitherSwitch.svelte
+++ b/src/lib/layouts/edit/controls/conversion/dither/DitherSwitch.svelte
@@ -11,7 +11,7 @@
   let { checked, onchange }: Props = $props()
 </script>
 
-<div class="stack gap-2" role="group" aria-label="Dither">
+<div class="stack gap-2" role="group" aria-labelledby="dither-switch-label">
   <div class="row gap-1">
     <Label id="dither-switch-label">Dither</Label>
     <MoreInfo>Dithering uses different dot densities to simulate shades of gray.</MoreInfo>
diff --git a/src/lib/layouts/edit/controls/conversion/dither/DitheringKernelDropdown.svelte b/src/lib/layouts/edit/controls/conversion/dither/DitheringKernelDropdown.svelte
index d1ee52b..467cc25 100644
--- a/src/lib/layouts/edit/controls/conversion/dither/DitheringKernelDropdown.svelte
+++ b/src/lib/layouts/edit/controls/conversion/dither/DitheringKernelDropdown.svelte
@@ -28,7 +28,11 @@
   }
 </script>
 
-<div class={cn('grow stack gap-2', hidden ? ['invisible'] : [])} role="group" aria-label="Dithering kernel">
+<div
+  class={cn('grow stack gap-2', hidden ? ['invisible'] : [])}
+  role="group"
+  aria-labelledby="dithering-kernel-select-label"
+>
   <div class="row gap-1">
     <Label id="dithering-kernel-select-label">Dithering Kernel</Label>
 
diff --git a/src/lib/layouts/edit/controls/dimensions/AspectRatioAlert.svelte b/src/lib/layouts/edit/controls/dimensions/AspectRatioAlert.svelte
index 893eca4..699bc76 100644
--- a/src/lib/layouts/edit/controls/dimensions/AspectRatioAlert.svelte
+++ b/src/lib/layouts/edit/controls/dimensions/AspectRatioAlert.svelte
@@ -1,10 +1,12 @@
 <script lang="ts">
   import * as Alert from '$lib/components/ui/alert'
   import IconAspectRatio from '~icons/material-symbols/aspect-ratio-outline'
+
+  import { INKCLIP_ASPECT_RATIO } from '$lib/constants'
 </script>
 
 <Alert.Root>
   <IconAspectRatio aria-hidden />
-  <Alert.Title>Image is not 1:1 ratio</Alert.Title>
+  <Alert.Title>Image is not {String(Math.round(INKCLIP_ASPECT_RATIO * 100) / 100)}:1 ratio</Alert.Title>
   <Alert.Description>You need to choose how to scale your image.</Alert.Description>
 </Alert.Root>
diff --git a/src/lib/layouts/edit/controls/dimensions/TransformControls.svelte b/src/lib/layouts/edit/controls/dimensions/TransformControls.svelte
index f17b156..b1ce89b 100644
--- a/src/lib/layouts/edit/controls/dimensions/TransformControls.svelte
+++ b/src/lib/layouts/edit/controls/dimensions/TransformControls.svelte
@@ -57,7 +57,7 @@
                   config.transform = config.transform.op(op as Operation)
                 }}
               >
-                <Icon aria-hidden />
+                <Icon aria-label={description} />
               </Button>
             {/snippet}
           </Tooltip.Trigger>
diff --git a/src/lib/layouts/edit/preview/FileSelect.svelte b/src/lib/layouts/edit/preview/FileSelect.svelte
index 6376e3c..1063c5c 100644
--- a/src/lib/layouts/edit/preview/FileSelect.svelte
+++ b/src/lib/layouts/edit/preview/FileSelect.svelte
@@ -12,4 +12,4 @@
   const filesCtx = getFilesContext()
 </script>
 
-<Input bind:ref type="file" accept="image/*" bind:files={filesCtx.files} />
+<Input bind:ref type="file" accept="image/*" bind:files={filesCtx.files} aria-labelledby="preview-section-label" />
diff --git a/src/lib/layouts/edit/preview/PreviewCanvas1x.svelte b/src/lib/layouts/edit/preview/PreviewCanvas1x.svelte
index ed3f5a6..e263a55 100644
--- a/src/lib/layouts/edit/preview/PreviewCanvas1x.svelte
+++ b/src/lib/layouts/edit/preview/PreviewCanvas1x.svelte
@@ -5,6 +5,7 @@
   import { cn } from '$lib/utils'
   import { drawQuantizedData, freshContext } from './common.svelte'
   import { getRenderedContext } from '$lib/contexts/rendered.svelte'
+  import { INKCLIP_HEIGHT, INKCLIP_WIDTH } from '$lib/constants'
 
   const renderedCtx = getRenderedContext()
   const hasRendered = $derived(renderedCtx.rendered !== null)
@@ -23,15 +24,17 @@
   <div class="bg-[#ccc] shadow-md rounded-lg p-2 w-fit relative" role="img" aria-labelledby="preview-1x-label">
     <div class="p-[3px] border-[1px] border-[#888]">
       <canvas
-        class={cn('w-[200px] h-[200px]', hasRendered || 'hidden')}
+        class={cn(hasRendered || 'hidden')}
         style:image-rendering="pixelated"
+        style:width="{INKCLIP_WIDTH}px"
+        style:height="{INKCLIP_HEIGHT}px"
         bind:this={canvasEl}
-        height={200}
-        width={200}
+        height={INKCLIP_HEIGHT}
+        width={INKCLIP_WIDTH}
       ></canvas>
 
       {#if !hasRendered}
-        <div class="col justify-center w-[200px] h-[200px] text-muted">
+        <div class="col justify-center text-muted" style:width="{INKCLIP_WIDTH}px" style:height="{INKCLIP_HEIGHT}px">
           <IconHideImage class="text-3xl" aria-label="No image" />
         </div>
       {/if}
diff --git a/src/lib/layouts/edit/preview/PreviewCanvas2x.svelte b/src/lib/layouts/edit/preview/PreviewCanvas2x.svelte
index dbb9f43..74be67b 100644
--- a/src/lib/layouts/edit/preview/PreviewCanvas2x.svelte
+++ b/src/lib/layouts/edit/preview/PreviewCanvas2x.svelte
@@ -6,6 +6,7 @@
   import { drawQuantizedData, freshContext } from './common.svelte'
   import { getFilesContext } from '$lib/contexts/files.svelte'
   import { getRenderedContext } from '$lib/contexts/rendered.svelte'
+  import { INKCLIP_HEIGHT, INKCLIP_WIDTH } from '$lib/constants'
 
   interface Props {
     fileInputEl: HTMLInputElement | null
@@ -43,11 +44,13 @@
   >
     <div class="p-[6px] border-[1px] border-[#888]">
       <canvas
-        class={cn('w-[400px] h-[400px]', hasRendered || 'hidden')}
+        class={cn(hasRendered || 'hidden')}
         style:image-rendering="pixelated"
+        style:width="{INKCLIP_WIDTH * 2}px"
+        style:height="{INKCLIP_HEIGHT * 2}px"
         bind:this={canvasEl}
-        height={200}
-        width={200}
+        height={INKCLIP_HEIGHT}
+        width={INKCLIP_WIDTH}
       ></canvas>
       {#if !hasRendered}
         <button
@@ -55,9 +58,11 @@
           ondragleave={() => (fileOverDragZone = false)}
           ondragover={() => (fileOverDragZone = true)}
           class={cn(
-            'col justify-center w-[400px] h-[400px] rounded-xl hover:cursor-pointer text-muted',
+            `col justify-center rounded-xl hover:cursor-pointer text-muted`,
             fileOverDragZone && 'outline-dashed',
           )}
+          style:width="{INKCLIP_WIDTH * 2}px"
+          style:height="{INKCLIP_HEIGHT * 2}px"
           tabindex={-1}
           aria-label="Choose file"
         >
diff --git a/src/lib/layouts/edit/preview/common.svelte.ts b/src/lib/layouts/edit/preview/common.svelte.ts
index 15e5239..9321b9e 100644
--- a/src/lib/layouts/edit/preview/common.svelte.ts
+++ b/src/lib/layouts/edit/preview/common.svelte.ts
@@ -1,3 +1,5 @@
+import { INKCLIP_HEIGHT, INKCLIP_WIDTH } from '$lib/constants'
+
 export function freshContext(el: HTMLCanvasElement) {
   const ctx = el.getContext('2d')!
   ctx.imageSmoothingEnabled = false
@@ -5,17 +7,19 @@ export function freshContext(el: HTMLCanvasElement) {
 }
 
 export function drawQuantizedData(ctx: CanvasRenderingContext2D, data: number[]) {
-  const imageData = ctx.createImageData(200, 200)
+  const imageData = ctx.createImageData(INKCLIP_WIDTH, INKCLIP_HEIGHT)
 
-  for (let y = 0; y < 200; y++) {
-    for (let x = 0; x < 200; x++) {
-      const colorIx = data.at(y * 200 + x)
+  for (let y = 0; y < INKCLIP_HEIGHT; y++) {
+    for (let x = 0; x < INKCLIP_WIDTH; x++) {
+      const dataIx = y * INKCLIP_WIDTH + x
+      const bitmapIx = dataIx * 4
+      const colorIx = data.at(dataIx)
       const color = colorIx === 0 ? 0xcc : 0x11
 
-      imageData.data[y * 800 + x * 4] = color
-      imageData.data[y * 800 + x * 4 + 1] = color
-      imageData.data[y * 800 + x * 4 + 2] = color
-      imageData.data[y * 800 + x * 4 + 3] = 0xff
+      imageData.data[bitmapIx] = color
+      imageData.data[bitmapIx + 1] = color
+      imageData.data[bitmapIx + 2] = color
+      imageData.data[bitmapIx + 3] = 0xff
     }
   }
   ctx.putImageData(imageData, 0, 0)
diff --git a/src/lib/layouts/write/WriteButton.svelte b/src/lib/layouts/write/WriteButton.svelte
index d870cf1..f72a5e7 100644
--- a/src/lib/layouts/write/WriteButton.svelte
+++ b/src/lib/layouts/write/WriteButton.svelte
@@ -4,6 +4,7 @@
   import { toast } from 'svelte-sonner'
   import { getDeviceContext } from '$lib/contexts/device.svelte'
   import { getRenderedContext } from '$lib/contexts/rendered.svelte'
+  import { BYTES_IN_A_ROW, INKCLIP_HEIGHT, INKCLIP_WIDTH, WRITE_TIME } from '$lib/constants'
 
   interface Props {
     onprogress: (inPropgress: boolean) => void
@@ -31,15 +32,15 @@
       }
     }
 
-    const buffer = new Uint8Array(5000)
-    for (let y = 0; y < 200; y++) {
-      for (let xStride = 0; xStride < 25; xStride++) {
+    const buffer = new Uint8Array(INKCLIP_HEIGHT * BYTES_IN_A_ROW)
+    for (let y = 0; y < INKCLIP_HEIGHT; y++) {
+      for (let xStride = 0; xStride < BYTES_IN_A_ROW; xStride++) {
         let cell = 0x0
         for (let xStroll = 0; xStroll < 8; xStroll++) {
-          const index = y * 200 + xStride * 8 + xStroll
+          const index = y * INKCLIP_WIDTH + xStride * 8 + xStroll
           cell |= renderedCtx.rendered[index] << xStroll
         }
-        buffer[y * 25 + xStride] = cell
+        buffer[y * BYTES_IN_A_ROW + xStride] = cell
       }
     }
 
@@ -53,7 +54,7 @@
     } finally {
       setTimeout(() => {
         inProgress = false
-      }, 2000)
+      }, WRITE_TIME)
     }
 
     toast.success('Wrote pattern to device')
diff --git a/src/lib/utils.ts b/src/lib/utils.ts
index d32b0fe..a27362a 100644
--- a/src/lib/utils.ts
+++ b/src/lib/utils.ts
@@ -4,3 +4,7 @@ import { twMerge } from 'tailwind-merge'
 export function cn(...inputs: ClassValue[]) {
   return twMerge(clsx(inputs))
 }
+
+export function showNumber(n: number): string {
+  return String(n).replace('-', '−').replace('Infinity', '∞').replace('NaN', '⁇')
+}