From a2e271a1da672e85e827abd3b34537452643787d Mon Sep 17 00:00:00 2001
From: Yrr0r <Yrr0r.g@gmail.com>
Date: Mon, 18 Jul 2022 22:16:52 +0800
Subject: [PATCH] more are working

---
 README.md | 27 ++++++++++++++++++++++++---
 const.txt | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 script.js | 26 ++++++++++++++++----------
 3 files changed, 89 insertions(+), 13 deletions(-)
 create mode 100644 const.txt

diff --git a/README.md b/README.md
index b4e3fba..67bd08a 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,32 @@
 # WebBLE with Paperang 
 
-The only thing this can do right now is print a self-diagnostics page.
+Prints redered markdown. Paper not padded after print finishes. Manual pull is required at the moment to get the full print area. 
+
 
-Connect, then hit print.
 
 ## Some useful BLE related constants:
 
 - Service ID: `49535343-fe7d-4ae5-8fa9-9fafd205e455`
+- Characteristic value to write to: `49535343-6daa-4d02-abf6-19569aca69fe`
+- Characteristic value to receive from the printer: `49535343-1e4d-4bd9-ba61-23c647249616` This is a NOTIFY character.
+
+
+
+## Some other tips on printing
+
+- BLE has a max data packet of 512, means 502 bytes of useful data. However, I found out that each packet should not contain unfinished lines otherwise they tear. So I rounded to 480 for 48 bytes per line on P1.
+
+## Other than just printing
+
+All send and receive data command byte are in `const.txt`. Send and receive has (almost) same data structure. When a packet is received, its also begin with 0x02 and end with 0x03. 
+
+2nd byte is command byte, then the first 5 and last 5 bytes are not very useful since I don't care about checksums so I discarded them. Then the last 11 bytes of whats remaining seems to be some kind of redundant addon data, so they are disregarded as well. Then only a handful of bytes will remain and they are easier to decode. 
+
+- Reading ASCII stringed values (SN, model, board version...) : Just do the right truncating and decode the rest as ASCII.
+- Battery status: Send command 16, only one byte will remain after all the truncating. That byte is the percentage value directly usable. Do not divide it again by 255.
+- Get heat density: Send 28, then look at the first byte returned. Same as battery status. Do not divide by 255.
+- Feed line: The printer will feed blank paper of a specific length. Send command 26, then immediately followed by the amount of lines(in pixel) to be fed encoded as payload data. 
+
+- Power-down time: Send 31, get a 2 byte integer. Notice it's little endian means reverse their byte order to read them. i.e. `[16,14]` or `0x100E` indicate 3600 seconds, not 4110.
 
-- Characteristic ID: `49535343-6daa-4d02-abf6-19569aca69fe`
\ No newline at end of file
+> Some commands in the list are not implemented on the P1 model. I do not know whether it works on any other model. 
\ No newline at end of file
diff --git a/const.txt b/const.txt
new file mode 100644
index 0000000..03677df
--- /dev/null
+++ b/const.txt
@@ -0,0 +1,49 @@
+PRT_PRINT_DATA = 0
+PRT_PRINT_DATA_COMPRESS = 1
+PRT_FIRMWARE_DATA = 2
+PRT_USB_UPDATE_FIRMWARE = 3
+PRT_GET_VERSION = 4
+PRT_SENT_VERSION = 5
+PRT_GET_MODEL = 6
+PRT_SENT_MODEL = 7
+PRT_GET_BT_MAC = 8
+PRT_SENT_BT_MAC = 9
+PRT_GET_SN = 10
+PRT_SENT_SN = 11
+PRT_GET_STATUS = 12
+PRT_SENT_STATUS = 13
+PRT_GET_VOLTAGE = 14
+PRT_SENT_VOLTAGE = 15
+PRT_GET_BAT_STATUS = 16
+PRT_SENT_BAT_STATUS = 17
+PRT_GET_TEMP = 18
+PRT_SENT_TEMP = 19
+PRT_SET_FACTORY_STATUS = 20
+PRT_GET_FACTORY_STATUS = 21
+PRT_SENT_FACTORY_STATUS = 22
+PRT_SENT_BT_STATUS = 23
+PRT_SET_CRC_KEY = 24
+PRT_SET_HEAT_DENSITY = 25
+PRT_FEED_LINE = 26
+PRT_PRINT_TEST_PAGE = 27
+PRT_GET_HEAT_DENSITY = 28
+PRT_SENT_HEAT_DENSITY = 29
+PRT_SET_POWER_DOWN_TIME = 30
+PRT_GET_POWER_DOWN_TIME = 31
+PRT_SENT_POWER_DOWN_TIME = 32
+PRT_FEED_TO_HEAD_LINE = 33
+PRT_PRINT_DEFAULT_PARA = 34
+PRT_GET_BOARD_VERSION = 35
+PRT_SENT_BOARD_VERSION = 36
+PRT_GET_HW_INFO = 37
+PRT_SENT_HW_INFO = 38
+PRT_SET_MAX_GAP_LENGTH = 39
+PRT_GET_MAX_GAP_LENGTH = 40
+PRT_SENT_MAX_GAP_LENGTH = 41
+PRT_GET_PAPER_TYPE = 42
+PRT_SENT_PAPER_TYPE = 43
+PRT_SET_PAPER_TYPE = 44
+PRT_GET_COUNTRY_NAME = 45
+PRT_SENT_COUNTRY_NAME = 46
+PRT_DISCONNECT_BT_CMD = 47
+PRT_MAX_CMD = 48
\ No newline at end of file
diff --git a/script.js b/script.js
index 3983cde..6d2e5c7 100644
--- a/script.js
+++ b/script.js
@@ -18,14 +18,6 @@ var simplemde = new SimpleMDE({
 });
 
 
-/*
-Some useful facts about printers:
-    service: 49535343-fe7d-4ae5-8fa9-9fafd205e455
-characteristics values are
-    Write to:  49535343-6daa-4d02-abf6-19569aca69fe
-    notify: 49535343-1e4d-4bd9-ba61-23c647249616
-On BLE, max size of one pack is 512, means 502 for each data pack.
-*/
 async function connect() {
     // Call browser popup to let user select device
     let printer = await navigator.bluetooth.requestDevice({
@@ -41,11 +33,25 @@ async function connect() {
     notify.startNotifications().then(() => {
         notify.addEventListener('characteristicvaluechanged', (event) => {
             let value = event.target.value;
-            let a = new DataView(value)
             // Convert raw data bytes to hex values just for the sake of showing something.
             // In the "real" world, you'd use data.getUint8, data.getUint16 or even
             // TextDecoder to process raw data bytes.
-            console.log('Notify:' , a);
+            let arr = new Array();
+            for(i=0; i<value.byteLength; i++){
+                arr.push(value.getUint8(i));
+            }
+            let payload = arr.slice(5, -5);
+            console.log('Command:' , arr[1], 'Payload:', payload);
+            if(payload.length < 11){
+                console.log(arr);
+            } else {
+                let decoded = '';
+                for(each in payload.slice(0, -11)){
+                    decoded += String.fromCharCode(payload[each]);
+                }
+                console.log('Ascii:', decoded);
+            }
+            
         })
     })
 }