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expo-ble模块测试demo 联调BLE模块 take 2

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Yudi Xiao
2025-12-10 16:43:22 +08:00
parent d2dcd39411
commit 56a5d0d45e
2 changed files with 27 additions and 16 deletions
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12
ble/protocol/ProtocolManager.ts
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@@ -5,13 +5,19 @@ export class ProtocolManager {
static calculateChecksum(frameData: Uint8Array): number {
let sum = 0;
console.debug(`[ProtocolManager] Calculating checksum for frame count: ${frameData.length}`);
// Checksum is calculated on all bytes except the last one (which is the checksum itself)
// But here we are calculating FOR the last byte.
// Example: 0xA0 03 00 01 01 5B
// 0xA0 + 0x03 + 0x00 + 0x01 + 0x01 = 0xA5
// 0 - 0xA5 = 0x5B
for (let i = 0; i < frameData.length; i++) {
sum += frameData[i];
}
console.debug(`[ProtocolManager] Checksum calculated: 0 - ${sum} = ${(0 - sum) & 0xff}`);
return (0 - sum) & 0xff;
const checksumV1 = (0 - sum) & 0xff
const checksum = (~sum + 1) & 0xff
console.debug(`[ProtocolManager] Checksum V1 calculated: 0 - ${sum} = ${checksumV1}`);
console.debug(`[ProtocolManager] Checksum calculated: 0 - ${sum} = ${checksum}`);
return checksum;
}
static verifyChecksum(frameData: Uint8Array, expectedChecksum: number): boolean {